TBE CRYSTAL STRUCTURE A4 of DIGLYOINE HYDROBROMIDE by (XA) ELSA PAULINE BARNE A.B., Syracuse University (1944) SUBMITTED IN PARTIAL FULFIi 1JMENT OF THE REQlImRkENTS FOR THE DEGREE OF MASTER OF SGIENCE at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY (1947) Signature of author..............0........ ............... 096 Department of Geo 6gy, May 23, 1947 Certified Thesis Supervisor *.hairman,000 Dpte o te on........ Gradu*teSuen*000 Chairman, Department Committee on Graduate Students The Crystal Struoture of Diglycine Hydrobromide 28 771G Table of Contents Page Introduction Literature and History of The Problem Material Figure I. Typical Habit of Crystals Exrperimental Method of Investigation The Unit Cell The Space Group Figure 2 Perspective View of Space Group Figure 3 Derivation of Equi-points Determination of Parameters First Patterson Projection (xy0) Table I De Jong I and F values Figure 4 Patterson Projection txyo) Preliminary Electron Density (xyo) Sample Structure Factor Calculations Figure 5 Electron Density (xy0) Second Approximation Patterson Synthesis Second Electron Density Preliminary Comparison of Intensities Figure 6 Patterson Projection *xyD) Figure 7 Patterson Projection (oyz) Figure 8 Patterson Projection (xoz) Figure 9 Complete Patterson Projections Electron Density Maps (xoz) and (oyz) Figure Ia Electron Density (xyo) Figure 10 Electron Density (oyz). Figure II Electron Density (xoz) Figure 12 Complete Electron Density Maps Atomic Positions Second Intensity Comparison Final Electron Density Figure 13 Final Electron Density Map (xyo) Table 2 Comparison of Observed and Calculated Intensities Under Three Conditions Structure Discussion Figure 14 Projection of Determined Structure Acknowledgment I 2 2 3 3 4 5 6 7 7 8 II 12 13 14 15 23 23 23 24 25 26 27 28 29 30 31 32 33 33 34 35 36 43 43 44 45 1 Introduction Due to the possibilities of the use of diglycine compounds in glycine separations and identifications and their usefullness as therapeutic agents it would seem desirable to obtain information on the structure of one such compound. By X-ray analysis the arrangement of the atoms in the crystal unit may be determined and the properties of the crystal may ble accounted for in terms of this arrangement. A crystal such as diglycine hydrobromide affords an excellent example of the use of a heavy atom in deft termining the phase constants which cannot be ascertained from experimental observations. Briefly the steps in the structure determination consisted of the following: I. Determination of the unit cell and space group. 2. Determination of the atomic positions. Literature and Hiat&ry of the Problem As far as is known no previous work has been done on the crystal structure of diglycine hydrobromide. The method of preparation of diglycine hydrobromide, diglycine hydrochloride (I) Refers to two glycine molecules, not glycylglycine. 2 and diglyoine hydrbodide has been reported by Walter S. Frost. Previous to this diglycine hydrochloride was reported by K. Kraut3 and F. Hartmann. Material Orystals and powder of diglycine hydrobromide (. H,, Br Nx 0, ) were presented by Dr. W. S. Frost of the Burnham Soluble Iodine 0, Auburndale, Mass. The material had been made by evaporation of water solutions of glyoine and monoglycine hydrobromide and glyoine and hydrobromic acid in theoretical quantities. Suitable crystals for x-ra4 work could no.t be found in this material so that crysta3s were grown by evaporation of a water solution of the diglyoine hydrobromide powder. The crystals are stable in the dry condition, very soluble in water yielding free hydrobromic acid on dissolving in water and are insoluble in alcohol and ether. The average melting point in I63 - 165. The orthorhombic crystals are elongated parallel to the c axis and are almost equidimensional in cross section. The typical habit of the crystals is shown in Figure I. (2) Walter S. Frost. Bis (Amino-Aoid) Derivatives. I. Diglycine Halogen Addition Products. J.A.O.S. 64 (1942) 1286. (3) K.Kzaut and F. Hartmann. Ann 133 (1865) 101. 3 Experimental Method of Investigation The colorless crystals of diglycine hydrobromide were investigated by means of the Do Jong, Weissenberg, precession and rotation x-ray methods. X-ray work with the De Jong method was done by M. J. Buerger. For the determination of parameters the Weissenberg method was used for the hko and hol reflections using OuX radiation. The precession method was used for the okl reflections using MoK, radiation. The Dawtoniethod was used to determine the intensities. The Unit Cell A o-axis rotation photograph gave o a 5.40 A. Measurements from a c-axis Weissenberg photograph gave a = 8.21 A b and 18.42 A. The number of molecules per cell is 4 and may be calculated as, Z Volume (density) Formula weight ( 1.66 x 10'" (5.40)(I8.42)(8.2I) 231.02 x IO~' ( I.66 x I0~" (1.941) ) = 4.12 (4) Dawton, Rl.H.V.N. Crystal Reflections. The Integration of Large Numbers of X-ray Proo. Phys. Soc. 50 (1938) 9I9-$25. (4) Klein, G.E. The Crystal Structure of Nepheline. Thetis M.I.T. (1947) 4 The Space Group The space grpup P-2, 2,., using the Weissenberg was determined by M.J. Buerger photographs. Characteristic absences noted indicating this space group are; hoo where h odd oko where k odd ol where 1 odd F 'Reflection Uondition for non-extinction h= 2n hoo Interpretation of 0II screw axis, component k oko .Symbol of Extinction E0I 2n symmetry elenet 2, /h screw axis, 2, component 1/ ool 1 2n 0OI screw axis, component '- 2, Only general positions occur in this space group. The equi-points with the conventional origin'of this space group are: x7z; '2-x, -. , '+Z; 2+x, }2-Y, Z; x, -i+y, i-Z. (5) M.J.Buerger. X-Ray Orystallography, John Wiley and Sons Inc. (1942) 83. (6) Internationale Tabellen zur bestimmung Kristallstrukturen. I (Gebruder borntraeger berlin (1935). - s st1 2 .2 s 6 4 F I ~-I------- - .1 -1--------------- - I I I 0 I I ~\ f '4 f I I 4+ i; 1 . 4+ 4+ WI I! If I. ~ 0 If It x1y3yx4yv iA-rn ~ F, 4 \Jr c- 7 However, for this work the origin was taken on a two fold screw axis because for the prism zone reflections the B terms of the structure factor vanish. In general simplification of the structure results if the origin of the coordinates to which the positions of the atoms are referred is taken as a symmetry center of the space group. With this origin the equi-points are xqy, z; iit i-y, '; }-x, i+y, i-Z; x, j, 9 z The space group symmetry elements are shown in Figure 2. Figure 3 indicates the derivation of the equi-points of the general position as used in this work. Determination of Parameters First Patterson Projection (xyo). Initially F values from a De Jong photograph taken by Me.J Buerger were used to obtain a Patterson projection (xyo). The F values were obtained directly as the intensities which are usually obtained experimentally were corrected for by means of a mechanical cam. The 2 atterson and Tinell method was used for all t' the Patterson projections for this crystal. The IFI values for the various hko reflections used in this summation are given in Table I. (7) R, L. Patterson and G. Tunell. A Method For The Summation of The Fourier Series Used in The X-ray Analysis of Orystal Structure. Amer. Mineral. 27 (1942) 655-679. 8 Table I. De Jong IFI Refleotion 020 040 Observed F 2.* .2 060 1.2 .2 080 4.0 and F values. t5 F 2 12 2 F 51%%w 14 34 14 -4 40 II -34 @100 0120 0140 I.I' 8.4 5.4 84 -92 54 -74 IO 120 7.6 76 130 140 150 160 170 180 190 1100 III0 1120 1130 1140 1150 200 210 220 230 240 250 260 270 280 290 2100 21I0 0.0 0 .5 5 1.2 5.I 12 6.6 4.0 8.5 1.2 10.6 51 66 0 85 2.0 12 106 20 7.8 .5 78 5 0.0 0 41 4.1 .4 1.2 5.7 5.7 I.I 1.8 1.8 15.8 2.9 7.5 8.5 4 12 57 57 II Is 18 158 29 75 85 16 2120 2130 1.6 .I 3.9 2140 5.3 53 2150 I.I II 11.7 I17 4 53 13 32 320 330 5.3 340 350 1.3 3.2 .4 I 39 87 0 22 -35 71 -8I 0 -92 -35 -103 -32 -88 -22 0 -64 -20 -35 -75 -75 -33 -42 -42 -I26 54 -87 92 -28 I0 -62 73 33 -108 20 -73 36 -57 9 Table I (ont.-) De Jong 1'1k and Reflection 360 370 380 390 3100 3110 F values. F Observed F .a .9 .4 .3 4.2 8 9 4 3 28 -30 20 42 71 65 84 3 280 167 17 3120 3130 7.1 .3 28.0 400 .2 410 3.9 .5 .3 .4 2 39 5 3 4 8.0 80 89 .9 131*00 9 -30 144 20 420 430 440 150 460 470 480 490 9.7 4100 0, 4110 4120 13,6 .8 510 5.7 .7 520 530 540 550 560 570 580 590 5100 5110 600 610 620 630 640 650 .4 11.8 2.9 .4 9.9 0 5.0 I.1 130 4 97 17 -14 62 -22 17 -20 98 0 0 136 117 8 28 57 7 75 20 V& 118 29 84lb? 4 99 0 50 II 54 99 0 71 -33 47 2.2 4.9 22 49 5.4 .4 6.0 0 4.5 0 54 74 4 60 0 45 -20 0 28 -7 I 660 .8 0 8 670 5.I 5I -70 77 0 67 - 0 10 The prism zones of this space group project as the plane group 0" which is shown in figure 3. Pertinent data for the interpretation of the Patterson projection of this plane group follows. No. Equi-pts Group Coordinates of egni-points Fourier Series *F' Series Data Data Group C', The 2atterson projection depends on F and not on Wt. Rep. ~ Ptst 2_X_1 F . Thus it is independent of the phase constants. The distance from the origin to a peak corresponds to an interatomic distance in the crystals. The Patterson projection (xyo) of one fourth of the cell (the motif) of diglycine hydrobromide obtained is given in Figure 4. In view of the high atomic weight of bromine in the molecule undoubtedly the intense peaks 1127, 1260 and 543 represent the br-Br interatomic distances. These points occur at the points Ex },} , 2y 1; and 2-x, 2y, re- spectively. With information from the above table the x and y parameters of the heavy bromine atom were determined as shown in the following table table. (8) A.' L. Patterson. Tabulated Data For The Seventeen Plane Groups. Zeits,.Krist. vol. 90 (1935) 5I7-542. 7 <) r Ot -5 9cz &C 1)-z 7,T / S-t 1%-k 7QC Cz KI~- L -7---t ~L %-t /~ crt -h ' &i S9, h I lt ~ I~ 1i 1i QSC 9X 4-5-z Ms~ -z~ " SLO t31bi _S'i -tit (E 111m, ti nos 94 c/ /4 L f *fr fl qL I Q - IA1 av 1 Y$ 4 1,0 I ~ SI -nio v)io vaS 3 1-C li 2c. 9, LE Sol , (-i f-)i 'g L-t ;6 41 1i i h LiIi 1J -Zl 0S 4s'r z Q 7)I1 ILf, 14 A* - iI ~L WL- 0-6 'tC -wIt Ccl Qt 1/' UZL ck - I. Ib I IT~ h/ 61 -1 b ~ s t - -? IQ I VI' 4 - - k~ ~ 'L cJC)t~ V iooI s.V 'U. S' cz Sji L(.c Q.i ,~u J0 5C :Er s/ - L Q. I ~ - S97% 41QIz ~~~~~~'~~~~5 L, tr -11. 5 I 'iIc 'k' it )SI Lh ~ LUii 7Si 07 ~ .1r55 9.4. tz LCh, 'A-t1E A/ j Z7 Z7. 1)5 4L. t £L Vz I'- +L 5S i- jJ~ r)6 Z I 44-V V"h ~*~ I I'~ L~ L rib t,1 '-r ? I 'I5T s , E~ L-r egL 0 -4 I ' -ZL 16I rh r a V, k I Liti 10-( Q,~ 1I sr Q t0 it -Z, Q, i "'I4 'l c 6(L J C) 0t Qu~ 5- .fuoL,: qvI 4''r S-S -6'r 06 7 Ch (t7 7)j Q- iL oir It 1t -1, Lit -S 5ft 17~ 5A C4i LL,. -S 4( , IS! /L r Ic Sti u-c j~ ~ 45 Q' 'qi-r i Y. '4S 0 Li 4~~'kr ,z 0/ QI ,bi * f~ i Of 2 GE' 12 Peak 2x+2 2y4j 2 x 2y x y 543 1127 -__ 1260 3 1f. Okz -. 2 reliminary Electron Density (xyo) in view of the high atomic scattering power (f) of bromine compared with that of the other atoms oxygen, nitrogen and carbon in the molecule it was assumed that the heavy bromine determined the phases. Since in projection the crystal is centrosymmetriaal the phases will be either o or T i.e. t or -. For the space group ,, D. , choosing the origin at a symmetry center the components of the structure factor for an atom in the general position are as follows: A 4kcos2Tt(hxtky+lz)+ cos21(h[ +x]+k[I-yi-lz) + cos2lT(h [ -x1+ k( +y] +1[ I')) B = 4fsin2(hxtky +1z) + sin2T(h[ sin24(h [- + k1i+y1l 1-z) + cog2i4(-hx-ky t1I[Jt ') -+x'+k -y'l-lz) + + sin2Tf(-hx-ky + 1[ +z) kor the various reflections these may be reduced to; Refl. hko hko okl okl hol hol A h+k = 2n 4cos2nhxcos27rky 4cos2'kxcos2rky k41 - 2n 4cos2irkycos2-iiz 4cos2kycos2flz htl -2n 4cos2rhxcos2Tilz 4cos2Trhxcos2mlz , A h+k = 2n+I -4sin2-,hxsin2rky 4sin2lhxsin'wky k+l -2n+1 -4sin2wkysin2rlz 4sin2TRkysin2-r1z h+1=2n+I -4sin2-ihxsin2rl z 4sin2rhxsin21z l B 0 0 0 0 0 0 . I13 hko :LI S . %)'X- Oi 4 ~ OX 43.cw A th C' ~ toL I~ f %-w ~r 16 aT a t.k )t * 4k(.7~ 1 / - - / N , / r -- 'N I- / -="N- -' / I' / ( = -- = ' = 'N S '. N" - N N N ' X14 I. 9 -3LL4 3r) *LC, i'1 7.S*'3 3t51 33 7l 170 1.1 2.9. 92.0 I Ii44 '15 1+5 3os' 11+4 z Is 1t 13 -141 I~ 1fj jO 34, yS 2.3 -S l ,-I 0)0 2*0. 1, i' '1 5S 9 ,4 s9 43 /- 77~ ' 2,2, 1'7 2J 2,72 s (, 1,17 19111 14?1 '. 7 24w1 1 A2 r 111 .V'5 ~ ~ Y 7 3 '5 ' 407 "3S (S' -/ ~ " .. -- L 1S -, 4'f 1342. to 110 J 1- Iv 2-P '' 15 2 2'0 -1 1 . 7 3- -i ' 11 ox 0 1~I7 k) A.3 ~ 143 3t3 449910 37 19/ 31 qo (.1) 114 qtlh'1 E 15 .(+0 It ~-t '17. 5 4 ' It 11 1,o) 111. 7,) 3r % '11 11.1f 33)11 -) 5c $ o 5 /(-5-4 (75 1.5 -7' 'r 141 1 24 14 51. 41 441 9t a.19 115- (7 t- lj o416 I, 3#t V (4 It' /(t2 2) 4)' 7 4s, I5 I-) r4 ) k4 '(7 '~ 2. ,60 Ill Il k ''0 I' I) A~ I 3S 31Vs 1*-; 11C 3 *,,' ' ? '4 ' I. .9 10/ 3 S2 I ' 1 (o(7 I/5 II 1 C 1/7 39 57- ID 1b43 -z9 (Dot) e'7 7 1fq 7 ?c !-1i ~ )-7 t (7 n'14 t 9 2$ 150 '' 7t4 2,1 7 9. 1* L'6 S i i 9) , 2 4 I. 74, -> 14 1~9'' 243 (14 1'~ ?3 ~ -3 53 Wi/ /7% V '3~ 54' -'4 '10 24s I. 57fl '-/3/~ 47 i M2+5 0 L11g is q5 0'L -7 -I "14 %.,S " 1 '() 249 I/ ,yo- 'P/ 5 ~ _71t'. ~ ( 1 2- '- in 374 17 7 ,-r, 5t 5 4 W1 'K 15 -ef li. "-0 ~ ~ (7 34 3% xqo P4 ~~C/ ~ '-/1~11 1o q 7 13 ('7 1,-7 - I )'ot, 1 0 V I I '+ 'y ''/ 1 od II Lg q-1 9m'~~~3d 1. 9~ ~ o i)q' tV -L fi jJS'~1 '4 I)-7O6' 1~ 10 ', 7-1 41 i9l 111 9 ~ ? '~ 3 i (7? - 14 5s .. p , 77 47 14 23 3 5 4 7~ ) 7.f )C 2. 3-. -C I lf/5 '1~ 1p 1315 7'/ 17 /7-4 irt# 1 c7 0- /3 ' -L' z2 (2 0. 1 2. tS to) I1f IL7 1 f cX S IV IS- \'i'' to. 17 N O 1 2 C'sAu\ it Q /7 lL13 1 O' io L 22 ? I 2.. ' 2.7 Xv .7 3 :15 A sample calculation of the determination of the phases is given below. Reflection Parameters x Y 6tructure Factor ces2irhx /m Phase cos21gy 220 .178 .034 -. 618 .910 130 .178 .034 .437 .802 4- With the phase constants determined in the abive manner and using the F values of Table I as obtained from the De Jong photograpj an electron density p (xyo) was made. The electron density map (xyo) of of the cell, the motif, is given in Figure 5. With 4 molecules per cell the position of 4 carbons, I bromine, 2 nitrogens and 4 oxygens (i.e. II positions) should appear in the electron density map of L of the cell. In the electron density map obtained the bromine appeared where it was put in the structure. However,many more than 10 other peaks are seen to occur indicating quite some error. Second ApproximationDue to the error just indicated it was necessary to obtain more x-ray data. This was done by means of the Weissenberg method for the hko and hol reflections using CuKa. radiation and the precession method for okl reflections usigg MoK.radiation. The intensities were determined by the Dawton method and corrections to obtain IF( are given below. Since intensities are obtained experimentally and F's or their squares are used as coefficients of a Fourier series for electron density maps and Patterson projections it is necessary to compute F's. As -1 is a function of sin 5- 16 (7 C ), sin must be calculated for all reflections. This was done by means of the formula sint (ah 2 + o*'-'l' (- ba = a*- c*5c, LP Reflection sins (cjTF CI. C 020 .0835 040 060 .1671 14.95 I5.6 .55 5.83 1.9664 .85 .10 .2506 .3342 0,190 *4177 0120 .50I3 0140 0I60 0180 02q0 .5848 .6684 .7519 .8355 022,0 .9190 .9823 HO .1026 .2085 130 .1565 .3246 140 150 160 170 .1915 .2290 190 IX90 Il,0 II20 1130 I I5,0 1160 II17,0 I,,9495 1.5873 .33 5.63 .93 .28 .I0 L, 2.52 5.43 I0 .30 I 18 I 31 4.58 .35 7*83 1.60 I.67 .19 .44 .098 .4046 .4950 4.21 5.75 9.43 3.82 29*59 14.65 .2675 .5945 25.73 .3071 .3470 .7050 .21 14.35 .3875 .8258 .9593 15.30 .I5 11.85 .4280 I.I04I .4690 I.2612 1.4265 1.5893 I.8843 .5100 .5500 .6325 .6799 .7163 .7576 .7987 1.9832 12Q0 .8407 I.9979 1.9356 I.7865 1.5552 I220 .9238 M.9432 11980 II,0 yklt-F .1688 .3482 .5500 .7861 1.0661 1.3910 1.7252 080 180 Q .90 6.58 .49 1.71 .05 .38 .II .13 .51 .08 .88 I.87 .86 7.26 .62 2.44 .08 .72 .22 .26 .99 .14 .81 1.26 .32 .30 22 -U . -kkY 32 47 6 7 II -- 43 -12 -56 - 25 -26 I -I9 2 0 -I3 4 19 27 7 15 59 6 -39 77 61 I -78 47 3 -69 29 2 I0 0 3 - a -19 -54 -16 -31 -6 -I? I 9 I 4 I 5 I -IQ 20 -7 22 II (9) M.J. Buerger and G.B. Klein. Correction of X-ray Diffraction Intensities for Lorentz and Polarization Factors. J. App. Phys. Vol. 16 No. 7 July 1945 408-4I8. 17 Refleotion aein BiflI! >--r-~' 200 2IO 220 .1874 .1920 .3950 .4057 .2050 .4365 1.33 6.19 44.I2 230 .2255 .4864 26.I3 240 250 260 270 280 290 .2510 .2805 .3130 .3474 .3838 .55I0 2.20 2.67 1.62 20.91 .420 .4579 .4964 .5745 .614 .6540 1.0746 2100 2110 2130 2140 2150 2160 2I80 2190 2210 2230 3IO 320 330 340 350 360 370 3100 3110 3I30 3150 3I70 .6299 .7220 .8268 .9443 1.2178 .8982 I.3711 1.6862 1.8282 1.9387 1.9962 1.8653 1.7025 1.1559 .9789 .4348 .2840 .6394 .6654 .6942 .7799 .8155 .2933 .3078 .3270 .3503 .3766 .4057 .5037 .5386 .6115 .6868 .7638 4180 4190 4210 .8402 .8778 .9540 24.21 97 I 28 4 9 I I 4 7 1.70 5.46 .86 1.40 .25 5.23 .36 .23 4.83 .16 .o5 4.40 .14 1.1085 1.1906 1.2870 1.3916 1.5103 1.7556 I*8657 1.7662 1.5583 1.3011 .6840 -17 19 9 II 15 2 1.10 3.00 .43 .73 .4292 .4509 3 3 I I 2 I .40 .31 1.06 4.66 .06 1.85 1.59 .18 .36 .10 .48 .58 -83 25 -38 38 -II .92 37.86 .36 -22 14 14 I .44 .27 450 460 -71 -22 -26 5 7 5 69 6 .54 .37 *51. .22 .30 *76 1.9189 51 .28 .29 1.4007 I*5433 1.8199 I/9906 -I5 -32 -88 .29 1.0230 1.0402 .6260 .8030 .21 F 2 I0 77 .14. 1.21 2.65 .4105 4120 4170 .47 .II .33 .69 .86 10.00 440 480 490 4110 .41 3.58 .7639 .8362 .9220 410 420 430 .4755 .5015 .5305 .5930 2.94 .24 .7071 .9163 .9241 .9470 .9864 470 1.60 3037 .53 2.51 19.26 12.71 1.21 1.68 I.I7 I7.29 1.51 3.62 .24 7.07 .92 2.22 .3749 .3772 .3840 .3953 400 zo I 2 12 14 13 -98 I0 -53 19 -30 -II 21 22 26 47 3 6 19 24 I -I10 .34 19 I 44 -12 .16 .26 I I 4.88 19 .17 I 8 -I0 44 -8 6*00 .08 2.79 24 49 0 II II I 3 33 33 12 -16 2.79 .34 .64 .16 .64 .40 6 I 8 3 2 ~16 ~I3 18 Refleotion sin vcy ) 510 .4705 1.2672 520 .4760 1.2890 530 .4852 .4975 1.3258 1.3755 14386 1.5144 1.6900 540 550 560 580 590 .I30 *5315 .5755 .6006 5150 .6277 .6560 .7173 .7852 5190 .9217 5200 .9579 600 610 620 .5624 5100 5110 5I30 650 660 670 690 6100 6120 6130 6140 .5639 .5685 .5867 .6156 .6338 .6765 .7006 .7536 .78I8 1.7809 1.8707 I 4.07 .14 5.12 .I8 4.87 .71 6.46 0 1.88 .64 .I9 .28 I.9429 1.9975 1.8449 .9604 .6481 .49 .24 .10 1.639I 1.6449 1.6590 1.7323 1.8332 1.8880 1.08 .34 .52 .95 I -I2 2 -14 1.22 .08 120 2.00 8 .I3 1.99 1611 .I8 I 28 - 7 .64 .10 .55 .48 .05 .74 .45 .93 4 0 5 2 I I 0 .09 128 6180 6190 .9390 .8163 .18 .45 .9728 .5016 .13 720 740 .6614 .6770 760v .7023 .7364 I.9539 1.9794 1.9996 1.9788 .66 .64 .79 .7778 .8257 .8789 I.8730 1.6457 .53 .21 1.2930 .0I .35 .01 .7498 .7544 1.9544 .45 .26 .88 .5I .7682 .7780 .7906 .806I .8388 8100 81208120 8140 .8582 .8794 .9019 .9509 1.7511 1.5669 1.5070 1.2894 1.1187 0*.7121 .16 .20 .I0 .30 .01 .16 .02 .23 .92 I 4 2 1.0882 .40 8 4 1.04 .38 .36 /9058 850 860 870 890 '19 I 1.9457 1.9439 1.9053 1.8723 1.8226 2 4 .37 .49 6170 800 820 840 4 I 0 34 21 -I214 .39 .75 6160 7140 0 II .18 ..8114 .8735 780 7100 7120 4 2 .I9 .18 1.3323 26 45 8 51 20 .48 1.9786 1.9990 1.8582 1.7241 .98 0 2.85 20 I .60 .20 .37 .07 1.29 1.27 I.58 .79 .99 .30 .37 .I8 .53 .O2 .24 .03 .26 *66 I -14 - 8 28 21 8 -20 ~12 -I2 ~19 - 6 -23 -I5 9 ~12 5 5 5 5 3 4 1 0 -23 -23 4 2 I I I 2 0 I 0 I 3 -19 -14 -II -25 -I8 -20 -I2 2 -I2 -8 -15 -3 I0 -3 I0 16 19 Reflection 910 930 940 950 960 980 990 9110 1000 IIO 1030 1050 1070 sin 6C%. .8445 .8428 .8599 .8690 .8800 .9073 .9235 .9606 ---.9382 .9451 .9602 .9818 Y LS' E%.5307 I.4764 1.4283 1.3646 I.2850 1.0764 .9456 .6227 .8228 *7630 i666 .4008 hol Reflection 002 004 006 101 201 301 sine .2850 .5700 .8550 .1706 .2355 .3152 I .50 .13 .15 .06 .12 .23 .10 .20 0 .05 .24 .65 .65 ( .19 .21 .08 .15 .25 .09 .12 0 .04 .18 .41 .26 I 261 -I8 3 I I 0 I -9 9 -6 8 I 0 I I0 6 7 0 0 4 8 13 10 0 I 2 I 'F 2OF O 86 -25 -22 .6423 1.6686 1.4618 28.97 .97 .83 18.61 I.62 1.21 74.44 .3564 13.15 40.67 2.52 .31 1.71 4.69 20.79 I*84 .31 2.30 1.77 .29 18.76 83.16 7.36 1.24 1L16 -II ~30 -27 -II 2.94 II*76 -34 11.76 9.76 -34 .5113 .7288 1.0067 .4011 501 701 901 .4899 .6714 .8551 1.3448 I.46II .90 .20 102 202 .3000 .3411 .4004 .6845 .8074 4.29 1.58 1.0042 1.5833 2.93 .10 .13 .33 1.9712 502 602 802 902 .5485 .6305 .8022 .8904 I.8787 203 403 .4668 5686 .6343 .8631 I.2587 503 803 .76 T1 Refeoetions 401 302 FP I.7700 1.207I I.6634 1.8894 1.4062 1.54 6.11 1.76 .10 .025 1.28 2.94 2.44 .19 .23 .40 7.65 2.93 .19 .035 6.48 4.84 9.20 7.08 43 -9I 27 23 .96 -31 -9 .92 -I0 1.60 30.60 II.72 .76 .14 13 -55 -34 -9 4 20 Reflection 404 504 .5776 .6004 .6549 .6822 .7379 104 206 304 6 sin & 604 .8007 .9680 105 205 .7186 .24 .18 1.36 .09 .32 505 605 705 .8523 .9078 .9685 200 400 600 800 .1875 .$749 .5624 .7498 106 206 306 .8601 2.64 .18 .96 1.28 I0.56 -10 -II -32 .72 2.60 0 0 -16 0 0 8 .33 0 00 .65 .43 .05 .05 .04 .03 .71 .86 .53 .15 I.05 .21 .14 1.72 .56 6.88 -26 .53 I.04 4*16 -20 0 .28 0 0 .37 0 0 1.48 0 0 -12 0 .5510 405 .9005 .14 1.7820 1.9859 1.9764 1.7773 .7367 .8051 Z F F 1.6980 1.9404 804 .8753 I 1.9970 1.9783 1.7560 1*4797 1.0726 .5459 .3952 .9163 1.6391 I*9544 1.4269 1.3193 1.1296 0 0 .I0 .09 .06 .03 .39 3.44 .40 19 - -6 .36 -6 .24 5 -3 .12 1.56 12 9 .84 -7 okl Reflections Reflection sin,5 - 020 040 .0385 .0770 1.0030 1.0119 .74 060 .II54 .1540 .1924 1.0270 1.0485 .2399 1.1122 .2694 .3079 1.1555 1.2072 1.2677 I.3376 I*10 IA.40 1.72 1.97 2.18 080 $I00 0120 0140 0160 0180 0200 .3464 .3849 .88 4.58 2.07 1.32 2.52 .76 2.76 1.63 10.04 5.21 2.32 1.30 .50 .81 3.63 I.5I 2.51 I.0154 .85 12.22 .95 1.08 17.43 1.24 1.37 1.51 27*79 I0.55 16.98 2.70 35.70 1.0767 031 041 051 061 .0875 .II24 .1165 .1328 1.0256 1.0275 1.0360 071 .1498 .1674 1.0459 1.0584 081 F 1I - 2.31 2.38 3*36 .67 1.88 2.43 4.2 .97 6.78 1.55 ll F 2 4 I -18 24 -14 4 2 15 8 5 2 4 20 -50 36 -28 20 16 -52 -26 -26 25 64 4 54 IO 26 -96 -47 le 20 21 Reflection sins I/p I/L I F F I ((F C>v[9- 0120 0132 0142 0152 0162 0172 0192 013 033 053 2.07 2034 3 4 2 3 7018 7017 2.30 9007 9006 I2.42 2.15 16*95 4.42 1.63 1.1427 I.3I21 2.11 2.37 2.35 2.43 .06 1.3483 2.28 .4284 1.3868 I.4278 2/I9 2.06 .1313 1.0350 1022 .1327 .1368 1.0359 1.22 1.0381 .I435 1.0420 I.0989 1.1314 1.23 1.31 1.88 .3904 .4093 022 032 092 0112 *67 .76 *40 .70 .55 178 0201 002 012 I 1.65 1.0861 .I852 .2033 0211 0221 .97 4.70 .15 2.18 1.0710 091 0101 0136 0180 0191 .2587 .3524 .3714 .2173 02488 1.2780 2.06 .72 .70 .80 1.22 2.06 2.94 .22 3 14 14 4 6 24 23 -24 -16 23 -48 -48 27 64 25 7 2 3 2 3 5 32 -20 23 18 2.16 2.22 .2997 .3170 1.1955 2.29 1.2207 2.34 .3346 .3524 1.2482 I.2780 2.37 2.38 .22 .13 1.99 125 I.67 3.43 .65 .40 I -21 -30 13 I0 .3884 1.3444 2.29 .25 .77 I -14 .I979 100813 I.0877 I.Ioo7 I.73 .62 2.68 I.16 1.79 1089 2.02 2.13 3.33 3.20 2.23 6093 2 8 I0 II 8 I 2 2 -17 37 -42 .2052 .2192 .2384 093 .2621 1.1468 0113 0193 .2891 .4153 1.1809 0213 .4494 004 .2626 014 034 064 084 094 1.1201 .48 .61 1.20 1.3995 14751 2.25 2.17 I.83 .13 .47 1.1474 1.1479 2.13 2.13 1.43 .2631 .2688 1.1548 2.17 1.69 .2868 1.1778 I.2018 1.2167 2.24 .18 2.30 2.33 2.36 .20 .03 .19 .3042 .3144 .3372 .53 1.85 5.22 7.24 5.45 .35 I.43 1.43 3050 4.52 4.24 .48 055 .09 .56 .3497 1.2524 I.2734 2.38 .03 .09 0134 .3626 I.2959 2.35 I.46 0154 0174 .3902 1.3479 .4192 1.4079 2.30 2.12 .48 .03 .10 045 .3370 .57 .3478 1.2520 1.2701 2.37 065 075 085 095 2.38 2.37 2.36 .45 .40 .33 .10 .38 1.69 1.36 1.22 0105 16 -35 I.1509 1.1731 .2656 .2824 073 0114 0124 7 .3547 1.2820 .3623 I.2954 1.3113 .3710 .3804 1.3290 2.35 2.33 .09 .30 I.0I .31 1.18 I 5 7 6 I I 0 I 0 2 0 0 3 2 2 2 0 2 43 -37 9 - 19 19 -39 34 -33 II 12 -5 12 5 -19 5 -9 -21 19 -I6 -16 9 17 22 Reflection sin - c--3kkQ 006 026, 0462 0106 0126 0146 .3939 .3958 .4013 .4384 . 5466 .4772 I/p I/L I 1.3554 1.3590 I.3703 1.4504 2.26 2.24 2,22 .95 1.4927 1.62 1.08 1.5406 1.90 .20 .I3 .08 .20 .80 F 2.91 .61 .40 .22 .48 .59 13 4 I I 0 I I 28 -I2 I0 8 -I1 I2 $10) M.J. Buerger. The Photography og The Reciprocal Lattice. ASxED Monograph No.I 23 Patterson SynthesisPatterson projections were obtained using the new above The three projections r(xyo), e (oyz), ande(xoz) cell are given in Figures The Br-Br vectors ar eemoi-d 6, 7 and8. (Fl , for 4 of the the (xyo) projection are the same as obtained in the initial Patterson using De Jong values although the rest of the plot is different. The complete Pattersons for all three projections are given in Figure 9. The originsof the three projections are seen displaced as in each case the origin is on the symmetry element, the two fold screw axis, and the relation to one another may be seen from the space group representation of Figure 2. Second Electron DensityUsing the new density Q (xyo) F values for hko reflections, a second electron was prepared. This second electron density resulted in the correct number of atomic position peaks. The first electron density e (xyo) seemt4to be much in error due to an insufficient number of terms having been used in the series. In the second electron density etxyo) I37 terms were used, whereas in the first 75 terms were used. 5v - to one only ,. Preliminary Uomparison of IntemsitiesA preliminary check of intensities for hko reflections was made using the atomic positions as indicated in the second electron density e (xyo) (f) and assuming an average value of the atomic scattering factor for the nitrogen, oxygen and carbon as it was impossible to de- termine which of these positions represented whiuh atoms. A sample calculation of intensity follows. ( / I I %~ j - N N 'N \ I I , I II / --' -- - / - I / - / 'N N - - / N / I N. N I N / / I / N I II JI / -I, I, Ii,-- / / '--- I, /1 I, I I, = I / I ~ ~lg 30 -7() (O 3-7 is 74 (0 )7 fir %4 ID 9f I .4 2 at Zt 4-Y. 7 Jo 3 'oA47 17 I 1 13 437 !a , 13 33 3 1 1r SAs 16- M' oil 191v, foi PIS' 13% lip.~ I1V. All 11% i 3.e "0 231 -20 4 IV9 / . 4 ,;7 Ir//- (, /o3 /419 103 /-3% /1 /-U ,3.% 'a-t 6 5'?y l 43 T'3 1,C L7 - 4 20 39 %I II r 2.103 N3 r 3' /' ir3 e i //b5 3/' i25 AMV 3o raG 3-7 :.16 32:. 4 /- f 1 2 36 99 7 /s- 4, 1y )( o s- irl - '? a/(, 2. 17 0 Ilt$ 439 l 30 1/6 /37 1I /S) :k 17 /t/k o 14 9 l.. s7 3 27 3.) j3 ~ '93 1- 09 17 '6 -7Y /0) $ 2- ~ 13 sf 3 ,L)3' 1, lo4 t3/2 /07 '* 3 ?.. 7-77 3zj 7 /' ly -7q bz2/73 / o t 9/7 9 0 D I' * r?1 27 4w X7 O 03 *31 99 2f 1/Pus, As- KI 3 2.3 3' 5 Ito 30 3 3% lra. 3v 25 Mf6 A6 92. 1 o 2-9 31 r 13. . lo03 28 )z ~7,yW/ 7 2-7 S,/ 3 to 33 /3 17 13 .2o ./ 41 4'6 / L 17 o % 3 9. l* 7I , 5-7 6 7 / 2-. 5-1 3#6 30 (,/ IN s 9 Io - 7(. -Y 5T . 3s- 35~ '75 91 161 i Ik 3 qV IT7 t o 1,'1 oy' :s- (c / IS ST $ e o-'i '79 -70 '77 'r S 31. 2.' 43 frt 30 (. 9 21. £3 oo / - -10 .0 97 5' '9 17 41 %9 it 6Si '77 ~r3 p. .3 s'/ 57 I 6 1 73 f 77 3 .rvtC 3 7 7-7 -f- £/5 8 33 2. 2/ (0 73 S. 1'57-f 2r 57-1. 37 970 (0-77 9 994. % Cf ~ Q 7 2% 7a S 7-7 3170 '7 o1 v If7 34 3o 6 ( 5% Sr 6/ 49 5W :t/ to 72 60e S il 73 S-s A 48 9-(1 l 2 ro as 31( (,7 7 ill 31 10 66y 7z at 15' l rso V, 7n 7a. 43 oin 1 it.7 390 s5*I 330 aIt la1 .7 33 37 Jl "s. '37 't %'5 13 f.gD 1 57 3 7 n - . 32.1 4-7 r 7 33 P4 3? 19- 1 1 s-o (0s r It a l t, 3 ' .s - L± 7 1 3 31 I o3,-so'3r 7 L-5 9z 7 0 '903 g M Y, A 1 rZ6 + 0.2. 390 2. 13 is- '69 5 3-a -atw.y it 4.P 56 s.~ ( 2-17 gr '3 "1 j*3 A 5-1 '# 3s- t- 32 i ag- &19? r39 f 3 30 5 N 7 '/ ( 23 3 ,7 5l 0 . 17 0 N I.7 9- 0to %% 3%0 275 377 o- fr .22 310 7 5-V (,3 ry 94 17 57 3 3A e 3 I%9 111 X..( ZO at / I- o 131 7(. 7) 2.1 . 97 le 116 1er rA.6 .rj, ,#- 2.'7 3 1 71 9 3! Is 161 . ,;. I ( 'Yr / : 5 6 9-f 6V 129 l16. I 3s- 17 133 :/ 57 t r- 2 *r 10 1( So 7 2 134 -1 *0 2.3 7 3 12 fvf .3 i3 9~7 67 ai- 2) -5/ 7 gy g 37 A ra 3% 3? 7 e 3 "1, 3 3/ 77 73 3r 7 r. i) 5-7 /6 (e i ) too 41 4 (, 17 f-L y i 1 19 94 // - ?2. &, 3 1 2. t 't 2t3 *71 7 n3 7 3c) 3 2.. 93 17 3 £ It 15, i I r1. yr 9r. fly / g) ,al-I irM 37 Mt I,jj b 2* Z 1351 i o$ /60 I Is / J 73 V .2.b 33 Z ii 10 4T/ 70" IT 1,o- ,S 2z2 30 19 96 63 g, r '7~ 7/ .0 '4I 4'4 3 7 g32 116 '/ 2- /it 1.1 3 2 I / (t fI 99 IS- 111as ir g 1o 4 36 J7 lot /so 0- 'A.6 37 o 4'os g ;3?. .7 /. 0 '9%1 )) 2. 3 .S X.5 30 M aoeA--Ae A~. JJ'tr ,j co'4.d 'r ow )cpi T c ~~ - . 4' o o 7 aoa e ~ c Amt t 2 ww us P- ri 30 O T - Pt4. * $C1 =t i 4_'-r -917 ~a 4 ie e s2 - 20y?? 0 ~ oo$A :1,.. An 14te Ci; ?C 275tiggh7It te- x = ? a~atg 3 3599a~a-scr ez.4 s $$nwawagen3R'a2112 pr 0 25 at 6-. V = I 'i5 is AL VI 5-t j\ t a LZ %k M 46 uI Ot h L6 . 4. iA L 4 a Lw a% 1 LA 16 %% % LL -,1 i 1.1 i V '1s . ''L iL 04 1L 111 % P) &4j 0L-r 161 Lt Ll is Sb Cs " -i 41 %1 Lc It as -LIof " oi c 1I E7i ,i Ct 4.1 5i 5. (l os / 4.4 as. S/ '1 - t ti.4. ,t it 'r. 6, <.7 r t 1, ( I t 6, ' I S C 5 i L ,' f 54 1! 6 b . I, %t 1 L '. Q -t4 1 1 S 51t 1/4. r ri Mt . 94, j L t ,c / ' (4. It S 7.* I hT ii O ha t 6, -h> *9 { t f -71 G I." ' L-r -I it ?L 1 / * -W S AL t 'ti ' -* ' S if 9 inti ;b Cz i. L L7' ty ( cl -t C, Ui -rr. I a -/ 1*r., f t'if Of iii ' A In 1 r /f. 4 S i f -f-t tSt " II o 4 - 1LEi4 ii i L, 'w Li 11 V i -5 I. 1 -46 i 1 6 LE AllE 4 % I IM 'n 6-L L 6 Ii 's 5 42 ii *4 4 I 6 -1 1 0 55 L5 -5* h1r kase -t r 4l -t 1 i TL Li ~It/5Ef 4, i.4 5r i 1. 1 -t- ot -)St i. b * 5 i s. t Ah 'ti T45I'I . ,I .5 5 . 4t. 1 1 1. it. Lt 'ih C /i-i (-r 1 VI *A-it 5l X1 1 C lL'. LAn 47p 151 Si1 4, 4 WI 1I' 10. *QE 414W CAI tm1 *Z'I fl E)l bti ti 'LAI I Mi Lt*rt it Si al1 c 6 Li it t -Vt Si ~i. i i4 l 'Z( 1 _-s- co u~ f ! LZ %. hai S' I., - Li J 11 Lt t 5( s L zttt'% it 1 us -Z+ '/ ti P r f.;t er u ( Q ') -s h(l t%- I t -- U VI 4L %tts1 L -t M Lr z3 "I L 7 sIX & -it GW L5I.5 95 (IL - to A -1 . I It . II'4L it5 t S-1- 63' ?,6 4L aI i. L VL 1 't 1, f. 2 -S ii L 'yx ch T i Lh -tL - 4, U-4 LA A-m1-1 L' WL +A Lh 56 It -I 4h It Elkli -i U66 kel II 6h 114 of h') LA kb 10, tal Lat i ILI hiL t-ti sja il r" 1101 All I '11 C6 bai t '1 Ug 315 Y Vf I k-U "s tf at90 40l Sit O)tIj it 4"1,1iEs Mvtil % -ti Al :% >>U QSQc %r 1 >Ch (15 Ti.... I1 Is IiiI I t "I f( 6/ .3 Tr 'IT s , r ', i ' i I 7 -S t - ,c> t it I j): t 5- f, ' I i .4eh% IU Li4C4 I - . 1 t L it 4, * 5 -tte -5 i 61' -r L/ Oi +I (I (L % tt 1 Uc L 7 0 ; 1I . -L,'.j '1 i aj t E 'i 1 '.1) ii (4 ,.$ Si (4 6.. S. t -Zji. I9si i1gi, Li At6 ti e-t Vr 4,, ii 14. L 4i Lt 51 r-+ .j C h L L 61 - I' 41 44 U Xt i 1 ,LLah i / iVi .. r iit K (QE lu LE Pi t i li Tr ~tj iih hi 6 TVi 1'i- 'iL1ki 1,4 SE., I.' El ' 11 *7'. i1.. L 1 f. (T /tJi I 'Iti' 'i i. fr j'e 04 9t J L '2't (. it 1Li "L i Lt 'M1 . '.C it 1 . %(#IsIt 4. 6 r. I M0 C L, 4 .'.' at,i ( '. Of8 aL Iri 'It t Of 0OC ? Zt At Ig -H i ',L (I- U QL aIi . 4 421- I, V I 4 -I a ~N'~ ~ 28 keflection m atom Parametbks x y mf Structuie Factor/m cos21hx '3 cos2Tky + 150 Br I 3 4 5 *178 .093 .108 .417 .067 7 8 9 .150 .470 .470 .417 .200 I0 .261 6 .036 .380 0430 .283 .180 .191 .113 .213 .283 .333 .430 41.51 7.03 7.03 7003 7.03 7.0 7003 7.03 7003 7003 7.03 .437 .834 .426 .779 -.867 0588 -.861 .913 .809 .588 -.982 -. 982 -.867 -.918 .918 .309 -.107 7.75 4074 3.22 .809 5.25 5.19 3.97 6.34 .960 6.34 --. 861 5.25 I.II 044 -.509 .588 =+ 33.80 The atomic scattering factorf, is determined for each atom for each refledtion as a function of sine. * The rough comparison of observed and calculated intensities is given in Table 2. Electron Density maps Q(xoz) and Q (oyz)Electron density maps t(xoz) andc (oyz) using the same pro. ceedure as was used for Q (xyo) were prepared and are given in Figure 10 and Figure II. The three complete electron density iaps all drawn to the same origin are given in figure 12. (II) M.J. Buerger and G.E. Klein. Correction of Diffraction Amplitudes for Lorentz and Polarization Factors. J. App. Phys. Vol. 17 No. 4 April 1946 285-306. (12) Internationale Tabellen zur bestimmung Kristallstrukturen. I. (Gebruder -Borntraeger, Berlin (1935). (IW) M.Je Buerger. Numerical Structure Factor Tables. America Special Paper 33. Geol. Soc. 'II I 7' / I I / / j / /,( j / *1 / ~ -, '. -- I N --. I I' I I 'I N ' - / / -. ......... N I, I' j 1,',~ ~ I I ,1 / I1 / -'' , / N I I I / I - / I ~ / I I / I(J I - 'I 22W -- / I ~ / I " N / N N - II I N 'N I N 6'7 51v t4 -1 Js 21 i / n '7 (. ~ 4' 117 35 9.-1 '01 Co9 3 S-01 '3 - I, ( 1 6 /01 IS I -60 In~5/ -0' 21 a' LM~ 18 S-1 9' 179 -II. Ivy -a -17 7y v~ 311.1 7 Z- ~ 16? i 33 1 2.0 V"1 ia-T 3Y 54 - 5or IV "1 5/ /3 7 13L3 'a is- fill r 170 40 #2 '#'# q( 2 43 2.23 aO'A ii' I)z- :L1 1 27 h~ Io 31 17 -7 S' I3. it 30 3C l 33 7% If -' 3 '7- i -! 5g3~ W{193 y/~ if~ ' tI I-7s 37 Itstq 110 3 '2~ ff. 31 51 999 ?3 9 9 M. O 10 j1 1/3 0, 41 12.. £( 11(a Iss5 9? 'q ~.-1 1+79 7 3 Z, 77 q7 r (.7 73 49-' /09f ill 9 I (. %6 5r 1) 13) '~ o. R7 ~3 117 1 '14 I ' I i IS ~S 3 -7r 1 '# If-. q.(6 a7 161~ 11 ' 3')7 j 3 13 5/ -3r ( 23) (.s 9 0. 174 )-S /1 14?2 7 1-734 Is -. I3 r 5-6 ~it 1 31 all1 4i' ity P 3.~ S144. '7/ I.SO Illi 1.1hi. GO, -lif 1z., toll lt3 4rz 71,6j W2 l? /9. q 12.3 -f7 '9f 1 9 ' i'3 3*1 as 1 '7 31~ '70 oI17 4,7 s~ 0 (O)S7 ~ Ip r' 6' 1 io7 1. -1 'Y2- '6 5' - d'( -77 xl I ZA q* .. 4 q Isr 7. 030 147 4 11. 1.S" %Isa r y' (. IS" 6,1 11 I It' -71 ~ sS' /3) Ix Ito1 X4 .( 11 sv ?,!, v I, /. to 3? / 5 -1 14 lot 1'3 '.rT -7 - L7 V7? 17 400 5 '7" v-'7 f41 5 6 . 5"t w% 1 L? Is to') 19 1? ol -* - 31 7 45- (3 ! 35 37 9Lt 7 1 10. Iff q 47 11 9 v- 1- 41 Y ? s991 4 2.( II I' i4' c I 16 r. Is-- 1 2 re 2.7 'I ;7 4 ilI I a7- . -7 1/'X0 7 2.1 V ?7 77 ill rs 2r IS 5i Z~ I lo D It 0 I -77 S t I 7 Z' XS- 1 '7? 1)6 tl. O 17 3F) 4* 7(p I(.7 fS/ 1 1- Mr I~ 5-1 '8 y Ia.9 141. 1F iV. s- 6 C 7 9 7 '- 41 ir3 -37 I S'- 1431 37 193 5 -. r 7 5, -7 31 STP 3o a Y4 to' a- I &6. s7 S-G 3T S3 6 fe7 S-1 76 v- 73 31 / 3 /-2 33 (. C7' 0- 'f 5 '4-t go 47 4A6 A 4# 26' a16 'z kn f 0 7f 31 7~7 X.5 '3 %r ~ ~3l4 ~ 4 IV*LC AX ao T VI iv fa GX 3I 7) lb )I 1(6 7f 2) f 11 1' 23 3*7 .243 5* 57 I'S~ za 122 7 XL 71# , -- y) ILI7 19 . s-) "c -3 f7 53 JL' Ii 1 / 1 I( 4 9 17 r? 92- 1t 31 k 3 /9 .2 3 3 3 itz -'s 31 371( 2, (7 ZO 36 54 /3 IL.>-, 91 25' /0 14 :(- '- ? ,g (~~ 4i ! 7 -~ 9- 1( 5-f 2.7 134f v 41 (.. 0 .2 3 '43 -4 'fX qf- -D3 ~ 7~~- X2 1 3 'A, j - ~ 94 160 1-(~ 7 f-/ 4.r 1 74~ 3 p - 7 771?7 4-7 17 t DJ5 3 5-S X. If V*3 Z*3v -j S1-3 7 1' ss 71., 4- '#. % 71 .5-s 9 -z 7? l, Ill 1/3 9- 1CO 3 1%s1 jo7 I;-f 21 4I it l 9'S~ ji 0 3 f; (0- I'l 19 c4.*9 (' ' S-6 9(. Ica 1 3.7- 7s 4~7r- C 5 (.- V 7q 3 1! S- Y-5 7 .27- 05 T1 tz /04 /11/3 r S-6 "3 71--s 73 b). '-' 1 5 7 -6 e L. - L~ 5' -'*7 do'a 6 9L'I# 79 3 7 951 fit) 1063 ( I *7(2 ,5' 9a 4 3r 0 :.- 3 (' 3 101#7 57? ((7 J;k ~ Y 4f,3 ;L 313l 191f Not0 (.7 17 91 ~24 2= 10 ~ ~~ I4 *1 ~ 77 p. % I 7 Wt / 'I / / - II II -I I 0 / / / / N ' , / - I - - I, / IIQ .1 11 - - / ,43 f, r .o P)~ P1 V- e '.C( D. r4 ol r N t: r4 - 4 -. 0 66 .0 V. N 4nM 4' - s- C Vk- - - , , q) F - CY'.P 3,z t-u JO- -V #9& Lc-1z r -3 won" -, -' -5"- P Y 30 N N N - / N I -. -. N ,~- /~ - - N / t 'I ~ N ) -~ / / \ \ \ - \ \\ ' ~\ N ~- - - \ N \ N N -. ~ N / \ ~ I - o _Q X) < 'X - _.SIA-0 ( . fl-A %A ' ~V~\ \\ it 4 .. 1' 1. 48 44 11n .44II ai4 4t 44 .' n . .4u 4.1 44 44 e 441 LA 65 " 7U _3 ( _h,, , .1 Wo L4. M * S3 Ch L ;4 LI Q. $T J't it EQ)41 oil (5 91 4, 7 jI9 . V.%nst4 .4 1' o # A t L -t ki -jzt r, t 0, S1 4 . A4.4 a 'n 5 1 4. s I3t Q'( C 't1 V t 4 1't 'tI#( 1 LI .5t L .1I 5 .4 t h w Lt jI It. JIS i4 s6 4 11L 'A A* W1 i 4 1 S -S, -S, %% L iv' 'it *,46O 0) 16( L0, .S C. 1 L3 -'j .'! 95 4.1 Ue 45 44 114 os1 12146 4m 2 1£. -,i. 4 l L L -5 r Q .1 at ist ii5 '1-1 4. 12 i 4,1 $(.5.It 11 4 i(I 44 iu I cl.1112 t. 01 4 s . 6 I a A i ti Ot 1VS 1w L 9 ' L6 A 6 . 44' 5 6L X41 5.4 'E o ,' ' 2 94. 4,1 4h 't 1 - 4.4 14 tI' (0. Q%. ')~ % 6 41 , 4, 6 V S +1 ES 0, tiSi .5 1L >L S6 11 44i, LL LSI 4.1 CZ Lb t4, A SL %i it L 1'5 I. j" .44 N4. hb 5h4b 4 )64, , -sS CI. Q 'f S, I ) 13AL ljQf54L bAL.0 LIS 4 (L ' .4 'i L s 4 i 4 5 'h (IL % 5 A t6 9 k I1I L.1 xl-I 1 6 .34 34 CS 1L 1C 4' .- E 41. . 15 SI 1A of I1L 4L 1: 1, L % I 1,6 24k-t h i 1 S '1+I' . 4C 5 il L, 4. L S b zo! -SO/ So/ L6 SL L 4.L 1. S 11 41 V 'L SL 46 %4 qg QI 1 30/ 4, 6 SS s. 4 + . L ff I 4't'1 q 17 s. 4. IL LI SLb .12(124 III 1.4 ' 91 I( oo4 sL 1' 91 f4 "4 A 4t 1 i Al 23 45 AS ,jS .., .1I 41) fQ1 '1 7/11.* 1 1' 46 A 3 4 L . L, LL it L 4 p, 7, 5 hi ( I' ' Vl a 5' W5s. S lbt u.1, h .-. 5 36 . 6 % Ab L hi S+y 1,6 ' i.S It .3 'L) +t 5.) 7C it, 4 (I& 4,, - .t S-4 I(r 4. S p-T. S L b, -, L 4-5 h1f.9 1 , '7 I. 4h L Z .L1 r t IC 6-2 Sth ht A. ~6 0' L-+ E 1-, 41 12' 4.IL.5A t' S*-1 9 ( 1 '4x -r.4 -Se 'OA IL I-) .Ah 6't I " 'T 1 *4 LI 9' c 12 11 CC 7.5 IL 'LL 13 sI. ui S-2 h. of .5 '4. 14..5'SS $I4412Cz ,0 '.1 4.7 a, 4.1 Lf 1. 4 'b C+ f, , LI r t -5) -h 4 -3 43 k1 ,1 04 7.f ;_ tih 4 21i34 , o 14 . Q j I. i .1 A . -1 0 VtCes t s 1 h% ti 46v it,414 it* + (gt si 11 1 t5 e1 t 16 M 13Le i it, o1 t ,s 4.01 s 4-i h u-S- --- -- tit I; t Coo 33 Atomic Positions- By comparing the three electron density maps and assuming the diglycine structure to be made up of glyoine molecules of known structure which of the peaks represented the oxygenpwhich $he nitrogens and which the carbons were decided upon. The atomic positions so obtained are: Atomic positions as determined from the electron density maps B 00 N 0 0 0 0 N 0 0 Y .178 .035 .089 .106 .268 .470 .196 .423 .380 .430 .430 .112 .333 .065 .283 *172 .145 .193 .475 .213 .423 .283 y .215 .370 .180 z *167 .333 .120 .I180 .I58 *363 .183 .417 .542 .484 .422 .443 .037 .037 .017 *127 .342 .350 .350 x z .072 .083 .161 .I44 .083 .370 .482 .092 .220 .433 *054 .092 .173 .233 .315 .123 .lo5 .408 .225 .100 .173 .400 Atomic positions referred to the same origin y Br 0 G N 0 0 .178 .035 .089 .106 .268 .470 .380 .196 .430 .430 .112 .333 0 .423 .283 0 .065 .172 N .145 0 .475 .193 .213 0 .423 .283 z .833 *833 .I20 .I158 .317 .842 .517 .373 .I58 .650 .350 Second Intensity ComparisonIntensity calculations were made using the parameters as determined from the electron density maps. A comparison of the observed and calculated intensities using a specific atomic scattering factor, f, for each of the atoms for each reflection is given in Table 2. (14) G. Albrecht and R. Corey. J. A. 0. S. 61, 5 (1939). Final Slectron Density I(xyo)-. Only foar sign changes were found from those determined by Br alone. The changes were for N320, 0 22 0, 6I0Aand An electron density map vno reflections. (xyo) made with tthese 4 sign changes showed a slight shift of parameters as indicated in Figure I3. The new set of parameters from the final electron density (xyo) are: Br 0 0 N 0 0 0 0 N 0 0 x .178 .095 *104 .278 .462 .200 .450 .072 .149 .472 .418 y .035 .380 .428 .430 .110 .338 .267 .170 .194 .213 .263 The agreement between observed and calculated intensities is somewhat improved with these new parameters as is shown for a few reflections in Table 2. I/ zo '(-. 'tf/7 UI2 ? 12-S I I 167 757 1.5s 10 314 ( Z3. 1 9 33S I2o 3qI t4 2-1 1.0 V2. 1 '+t 7 -77 1, 10 lo il l (00 i Il1/) 73 13 4 q(. , 5 f q7 5 7-7 I~t 77 s*'f (3 '7 3 L(.L- t0 0+7 (f 7r ~ ( 9 C L( ILI j. 90. V 14 sr 13 Tq )31 9b rto /4, 6 1 '1'x 6/ /10 7 r v ' 7y k 2.? I ' ~ 11(/ I r" 5-9 ~ So 37 L /'I ( 7o r/ ~f CV (( 7 9 /.Lx \797 t272 (3 70 g Co 703 5? 7' '7 3" 34g 7 '17 7/ '0' t ' t' ' . (7 of 1 A 9-D 70 Lt(7 Jig S-f 7 77 !. 55 1,1 !; 7~y . " 'm2 ~)37 Of 51 37 17 0 1 'L 11 9 S 7 1 It 1 10 1 1-L ~ ~ I I 1 33 77 9' /f 75 23 1) 10 ;ZS 1- 19 5 2,7 s7 1o' C7 4+ 7 17 1 3 1?, 19 37 q S( 2 -7o 97 4' 7S '7 l /12 57 3) t4 43 ~3 '74; 5 - Is 0( If. s 03 20 7 4L fLO/ 2/'f A3 y(2 Xb 31. S13 71 I-) 3/ o.5 Z4 Dt.. o; '3?.I1. 7- TS -Is 7 ) 711.7 7 07 it4' S. 7 '( L4. 377 L7 0 zs 21P T14 fix.5, ~ ? £#) 7,t ;Z,? (r9 7 b~ 57U '6 4 p 7 1011 r 7L T U)l . 1o-1'3 S' (.1% 17 3s.3 1V t 10) '79 is to7 (./ 35. y (~ It); -73 7, 7 4 /0 / X '7T C7 (124, 1)) i0 '3 3 7s it5' 2,1 IN 13 10 . r7 f16) 0 17' '43 74A 7) -7 .71 243' 113 v -- I , I. 167 %.3 1.00 71' 'f 30 Iqr- y 5(~ ;3 '63 M3 193 S7 II Z30 13 9 -/ f 004 ( '215 9 (ii xo 1 37 (. I, 3Cs s3. I'7r, 1.L Y s'3 7 1-357 -0 3s (C / z&~ ,D2. r '/ 7- IU 4 - - I -k-s >. 'L4 a 7: zl , x'? I 'I-Ir f I C F, ~j-~ E (~ C.~3 cJ1 36 Table 2 Comparison of Observed and Calculated Intensities Under Three Conditions Condition I. Rough comparison using an average scattering factor f, for oxygen, nitrogen and carbon in intensity calculations. for oxygen, nitrogen Condition 2 Intensity comparison using correct f and carbon as well as for bromine. Condition 3 Intensity comparison using final x and y atomic positions and condition 2. Reflection Observed I Observed Y401 k~o 220 NO 150 230 160 270 040 020 180 330 140 II00 210 080 130 0120 410 530 470 450 II 510 290 3130 2100 44.I 37.9 29.6 26.I 25.7 20.9 15.6 I5.0 14.4 I0.0 9.34 6.6 6.2 5.8 5.75 5.6 5.2 4.9 4.7 4.4 4.2 4.1 Calo.VI/ 4 Condition Cale. I/ 4 Condition Cal. 4/4 Condition I 2 3 41 36 42 37 29 32 31 42 39 34 32 32 40 34.9 33.8 29 25 30 24 24 20 19 16 16 I5 15 23.3 23.3 22 27* I 20.9 2I.0I 16.6 14.7 20.1 9.6 20.6 31 33 29 29 25 21 25 22 25 19 12 17 I7 14 18*7 20 18 20 14 13 13 15.8 19 20.1 II 13 1908 II 14 15 14 I4.9 3.4 12 3.0 II 17 12.9 16.3 2.9 II I4.7 31 25 21 24 22 23 17.5 I2 13 18*7 18 18 19 17 19 12 15 14.6 14.6 I7 IS 17.8 14.3 37 Refleotion 250 350 240 560 490 1120 260 280 4110 200 600 340 620 3110 0140 8140 2230 190 0160 1200 760 3100 5200 6140 3170 540 720 1050 1070 740 580 640 4210 060 670 7400 1180 910 III0 5110 4190 6120 2140 Observed I 2.7 2.7 2.2 1.9 1.9 1.7 1.6 1.6 1.6 1.3 1.2 1.2 1.2 I.I .93 .92 .92 .90 .85 .81 .79 .76 .75 .74 .73 .71 .66 .65 .65 .64 .64 .64 .58 .55 .55 .53 .51 .50 .49 .49 .49 .48 .47 Observed V4-0I 8alo. \FI/4 Condition I I0 I0 9 9 9 8 8 8 8 7 7 7 7 7 6 6 6 6 6 6 6 6 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 13.8 13.5 12.4 13.4 13.7 13.4 7.6 9.6 12.8 12*5 7*98 7.8 13.2 I3.5 II.*8 Galo. \i/4 0 alo0.NX/4 Condit ion Condition 3 2 12 10.6 12.0 14.8 13 13 I0 I0 I3 I0 I0 II 14 9.5 14*9 IS.0 15 12.4 10.6 14 I0.5 I0 6 7 13 13 II 12 II 17 17.97 1106 19 8.2 9.8 15*9 11.3 12.5 8 12.5 15 13 II 13 14 I0.05 I0 6*96 12 I0 12 8.36 7.88 3.6 8.7 7 8 14 6 9 12 9.7 10 5.0 II 6 7 I0 9 I0 13 38 Reflection Observed I Observed I40ICalo.[Fi/4 Condition I Calo.JIf/4 Condition 2 6180 800 6160 2210 3150 2130 780 5190 1150 .45 .45 .45 .44 .43 .41 .40 .39 .38 12 13 II II 9 8 7 12 7 320 4170 420 0100 1220 .36 .36 .36 .33 .32 3 12 3 5 8.5 870 370 360 2180 5I00 .30 .30 .29 .29 .28 8 6 7 9 4.5 0200 .28 820 400 440 5130 2110 980 8120 2190 7120 170 9110 .26 .25 *25 .24 .24 .21 .23 .22 .21 .21 .20 6 4.5 5 9 4.5 13.9 10 7.9 5 5 II 850 .20 3 690 590 6100 4120 6170 .19 .19 8 7 .18 6 .18 .18 3 6 8100 840 .16 .16 7 7 430 940 460 520 2160 6190 .I6 .15 .14 .14 .14 .13 5 II 3.5 5 5 8.6 930 .13 6 1170 960 1160 .13 .12 .11 6 5 5 10 Calo.\I/4 Condition 3 39 Refleotion Observed I Observed \(II Cale. fV/4 Condition I alo.{ i/4 Condition 2 k C) 2150 990 4160 5150 860 660 0180 0220 1190 610 480 950 6130 1130 I010 8110 890 7140 4I00 3120 390 380 2120 4140 4200 550 570 5120 5140 6110 6150 I000 .II .I0 *I0Q .I0I .10 .10 .I0 .I0 .08 .08 .06 .06 .05 .05 .05 .02 .01 .0I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6.5 6.8 5 5 6 6 2 4 3.6 2 7 6 4 5 4 2 Gale. \Ii/4 Gondition 3 Comparison of Observed and Calculated Intensities under Condition(2) Reflection Cale. fi/4 Cale. I/Io' Observed I OK 061 041 41 34 27 032 031 33 I7.4 15.4 002 31 27 012 28 12.5 5.7 5.2 7.0 071 19 0120 18 053 21 040 073 033 17 I7 II.6 4.6 6.4 4.6 12.4 12 7 7 4.7 4.6 3.3 3.4 3.2 2.7 2.4 2.4 051 0101 II 15 1.9 3.6 022 12 2.3 2.3 093 092 0140 080 014 14 13 3.1 2.7 12 2.3 2.2 2.1 2.0 14 3.1 2.7 034 15 3.6 004 0160 0152 18.7 5.6 1.9 1.9 081 006 0122 0146 0200 A620 0181 0221 0112 'II II II 20 I0 12 8 1.9 6.4 1.6 2.3 1.9 1.85 1.7 1.4 1.3 1.20 .97 995 .8 .8 I.0 .8 I0 I0 1.6 1.6 12 8 5 4 5 7 2.3 .4 .25 .7 .7 .7 .76 .7 .67 .4 .6 .8 10 1.6 091 0213 7 II 0180 0132 0193 0134 3 .8 1.9 .14 .8 .6 .65 .55 .5 .5 .5 .5 .5 .5 .4 0201 0191 060 - 20 18.5 28 17.4 OI3 0142 045 065 0211 075 0105 085 0192 0162 084 7 8 9 I5 4 9 9 5 7 5 5 1.0 I.o 1.3 3.6 .25 1.3 1.3 .4 .8 .4 .4 .4 .4 .00 .25 .2 .2 Reflection calo. \I/4 Calo. I/IO Observed I Q.)k . .8 0,II4 OIZ6 064 0172 0113 046 0174 095 0131 7 9 094 5 7 9 1.3 4 4 0124 0154 0106 024 3 4 2 6 7 5 3 .2 .14 .25 .2 .2 .I3 .16 .I13 .57 .8 .13 .4 .I .14 .4 .8 .25 .06 .03 .03 .03 .08 .25 0 1.3 .I 42 Comparison of Observed and Calculated Intensities Under Condition (2) Reflection 201 002 I0I 203 102 302 301 403 501 202 502 Observed I ObservedYl 28.97 13.15 6.11 6038 5.38 3063 2.47 38 32 22 4.29 2.07 2.93 1.71 12 I0 2052 1.59 1.76 1.71 I.33 1.31 1.58 I.54 40067 1.24 1.17 1.02 .98 7.4 16 7.0 6.1 13 .91 .84 .73' 504 401 206 .28 901 .20 204 .18 .15 404 205 405 505 605 803 601 402 702 .025 0 0 0 1905 12*4 7.8 .71 .53 .53 .43 .33 .33 .31 .14 .13 .I0 .I0 .09 .05 .05 .04 .03 13.5 8 7.5 705 400 104 802 602 503 29 25 1.26 .83 902 36 31 13 1.36 1.05 .97 i90 15 Calo. fI 9.5 8 304 600 004 701 006 200 800 105 Observed 6tIF .95 .73 .66 5.9 5.7 5.5 5.0 4.4 4.4 3.9 .57 .57 .56 .53 3.4 3.4 .44 .43 .39 .37 .36 .32 .32 .30 .22 .22 .20 2.7 2.5 .17 .16 3.3 3.2 2.3 2.3 2.2 I.9 1.9 1.8 1.3 1.3 1.2 1.15 .95 8.3 10 1805 13 23 21 I0 13 7 9 9 6 6 9 3 4 4 5 7 .22 2 7 5 8 6 8.5 Structure Unit cells a b 8.2I A 18.42 A o 5.40 A Space group: Atomic positions: y I z Br .178 .935 *833 0 G N 0 0 .095 .I04 .278 .462 .200 .380 .428 .430 .110 .338 .833 *120 .158 .317 *842 .450 .517 .373 .158 .650 *350 o o .072 N 0 .149 .472 .267 .170 .I94 .213 0 .418 *283 Discussion The above structure can only be regarded as an approximate structure. The atomic positions are in some error due principally to the overlapping of the atoms in projection. The atoms could not be further resolved as only zero level photographs were taken so that only projections of the cell could be obtained. No account has been taken so far of the position of the hydrogen atoms in the structure or of their contribution to calculated intensities. A projection of the determined structure on xyo is given in Figure 18. Here the shape of the glycine molecule may easily be seen. Ok Ce rL rf %rrL-ANV Ol 45 Aoknowledgment The writer is indebted to Prof.I. J. Buerger for the suggestion of diglycine bydrobromide for orystal struoture determination. Suggestions during the work and reading of the manuscript were most helpful.