Supplementary Material
Vibronic Coupling in Asymmetric Bichomophores:
Experimental Investigation of Diphenylmethane-d5
Nathan R. Pillsbury,1,a Nathanael M. Kidwell,1 Benjamin Nebgen,1 Lyudmila V.
Slipchenko,1 Kevin O. Douglass,2 John R. Cable,3 David F. Plusquellic2,* and Timothy S.
Zwier1,*
1
Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084, USA
Quantum Electronics and Photonics Division, Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, CO 80305-3328, USA
3
Department of Chemistry and Center for Photochemical Sciences, Bowling Green State
University, Bowling Green, OH 43403-0213
2
Synthesis of DPM-d5
DPM-d5 was prepared by reduction of diphenylmethanol-d5 (benzhydrol-d5) using
the hypophosphorous acid-iodine system as detailed by Gordon and Fry.1
Diphenylmethanol-d5 was obtained by reacting the Grignard reagent of bromobenzene-d5
with benzaldehyde in diethyl ether.
1. Gordon, P. E.; Fry, A. J. Tetrahedron Lett. 2001, 42, 831.
Table S1. Rotational constants and distortion parameters from least squares fits of the
ground state and S1 ← S0 spectra of DPM-d5. The S0 parameters were determined from
fits of the MW spectrum. Other parameters were determined from the UV spectra using a
combination of techniques that made use of genetic algorithm and non-linear least
squares fitting routines (see text for details).
S0
S1
S1 T10
S1  10
A” / ΔA / MHz
1884.0205(8)
-1.509(3)
-2.470(13)
-9.810(8)
B” / ΔB / MHz
404.6237(6)
-1.367(2)
-1.398(2)
-1.461(3)
C” / ΔC / MHz
399.4791(4)
-4.280(2)
-2.421(1)
-4.525(1)
ΔI” / ΔΔI / u·Å2 a
-252.160(2)
9.26(1)
3.029(6)
8.586(3)
ΔJ / ΔΔJ / MHz
5.4(1) x 10-5
----
----
----
ΔJK / ΔΔJK / MHz
2.00(7) x 10-4
-3.44(7) x 10-4
-4.3(2) x 10-4
-2.9(2) x 10-4
ΔK / ΔΔK / MHz
2.96(2) x 10-3
-6.34(9) x 10-4
-3.0(1) x 10-4
-9.6(2) x 10-4
δJ / ΔδJ / MHz b
4.0(3) x 10-6
-1.4(3) x 10-5
----
----
δK / ΔδK / MHz b
-3.6(2) x 10-3
7.3(5) x 10-3
-5.0(7) x 10-3
----
Origin / cm-1
---
37363.94(2)
Band type / %
60 b / 40 c
66(2) a / 3(1) b /
31(2) c
37389.32(2) /
+25.38(2)
63(2) a / 3(1) b /
34(2) c
37384.73(2) /
+20.79
57(4) a / 7(2) b /
36(4) c
υG / υL / MHz c
---
21.3 / 5(1)
21.3 / 6(1)
21.3 / 5
T1 / T2 / K / wt d
2
φ / θa/bc / χ / º e
---
4.3(1) / 17(1) /
0.61(1)
-22(2) / -0.813(7) /
57(2)
3.9(1) / 13(1) /
0.54(3)
-32(1) / -0.82(5) /
67(1)
4.8(2) / 22(2) /
0.12(4)
-11(2) / 1.17(3) /
47(1)
870 / 280
459 / 290
360 / 290
Assigned /  / kHz
40 / 3.5
defect ΔI = 505,379(1/C - 1/A - 1/B) where A=ħ/2Ia and Ia is the moment of inertia about the a-axis, etc.
reduction needed since standard deviation, , increases to 208 kHz in symmetric reduction in contrast to
DPM and DPM-d12 where little difference was noted.
cVoigt lineshape includes the Doppler (Gaussian), υ , and Lorentzian (lifetime), υ , components (FWHM).
G
L
dTwo temperature model: exp(-ΔE / kT ) + wt · exp(-ΔE / kT ).
1
2
eEuler angles represents the upper state frame rotation relative to the lower state with negative angles corresponding to
a counter-clockwise rotation.
aInertial
bAsymmetric
Table S2. Assigned lines in the MW spectrum of DPM-d5.
BT
B
B
B
B
B
B
B
B
B
B
B
B
B
B
B
C
C
B
B
B
C
B
B
B
C
B
B
B
C
C
B
B
B
B
C
C
B
C
B
B
a
Expt. Freq.
(MHz)
J'Ka'Kc'-J"Ka"Kc"
8
5
5
9
6
6
7
7
11
11
4
8
8
5
9
9
9
9
6
10
10
10
7
11
11
11
8
12
12
12
12
5
9
13
13
13
13
6
10
10
2
3
3
2
3
3
3
3
2
2
4
3
3
4
3
3
3
3
4
3
3
3
4
3
3
3
4
3
3
3
3
5
4
3
3
3
3
5
4
4
7 - 7
3 - 4
2 - 4
8 - 8
4 - 5
3 - 5
5 - 6
4 - 6
10 - 10
9 - 10
0 - 3
6 - 7
5 - 7
1 - 4
7 - 8
6 - 8
7 - 8
6 - 8
2 - 5
8 - 9
8 - 9
7 - 9
3 - 6
9 - 10
8 - 10
8 - 10
4 - 7
10 - 11
9 - 11
10 - 11
9 - 11
1 - 4
5 - 8
11 - 12
10 - 12
11 - 12
10 - 12
1 - 5
7 - 9
6 - 9
OMC = Observed Minus Calculated
1
2
2
1
2
2
2
2
1
1
3
2
2
3
2
2
2
2
3
2
2
2
3
2
2
2
3
2
2
2
2
4
3
2
2
2
2
4
3
3
6
2
3
7
3
4
4
5
9
10
1
5
6
2
6
6
7
7
3
7
8
8
4
8
8
9
5
9
9
10
10
0
6
10
10
11
11
1
6
7
10806.321
11429.988
11430.193
11589.752
12233.897
12234.373
13037.657
13038.609
13148.949
13442.218
13589.625
13841.210
13842.926
14393.700
14644.491
14644.521
14647.331
14647.362
15197.765
15447.431
15451.894
15451.943
16001.811
16249.943
16250.007
16256.699
16805.834
17051.921
17052.029
17061.584
17061.689
17357.031
17609.832
17853.264
17853.438
17866.782
17866.958
18161.094
18413.772
18413.804
OMCa
4.8
-4.3
-3.0
-5.5
1.6
1.9
3.3
2.9
3.8
2.2
1.4
-0.1
0.2
0.7
-4.9
3.7
-7.5
3.6
2.5
-4.7
-6.1
4.2
1.7
1.4
-2.5
-3.9
0.4
2.3
-2.5
2.8
-4.5
-2.8
0.1
3.0
-3.2
3.3
-0.5
-0.6
-3.0
7.9
Figure S1. Rotationally resolved UV spectrum of the vibronic band, S1 10 of DPM-d5.
Residuals from the fit are shown below the spectrum.
Figure S2. Rotationally resolved UV spectrum of the vibronic band, S1  10 of DPM-d5.
Residuals from the fit are shown below the spectrum.