Journal of Molecular Modeling
ELECTRONIC SUPPLEMENTARY
MATERIAL
Triplet fluoranthenes:
aromaticity versus unpaired electrons
Svetlana Marković*, Jelena Đurđević, Svetlana Jeremić, Ivan Gutman
Faculty of Science, University of Kragujevac, 12 Radoja Domanovića, 34000 Kragujevac, Serbia
Corresponding author's e-mail: mark@kg.ac.rs
Results for diradical 2
Fig 1 Optimized geometries with indicated bond lengths (Ǻ) for 2 as singlet diradical (2OS) and
pure diradical (2T)
Table 1 Distribution of spin density, obtained by NBO analysis, in 2T (see Fig. 1 for atoms
labeling)
C atom
Spin density
1
0.214
2
0.227
3
0.191
4
0.204
5
0.305
6
0.220
7
0.209
8
0.264
9
0.266
10
0.369
11
0.329
Fig 2 SOMO (a), SOMO-1 (b), and spin density map (c) for 2T. In the spin density map the blue
and red regions indicate the highest and lowest spin density values, respectively. The same holds for
Figs 5 and 8
Fig 3 -HOMO (a), -HOMO (b), -LUMO (c), and -LUMO (d) for 2OS
Results for diradical 3
Fig 4 Optimized geometries with indicated bond lengths (Ǻ) for 3 as singlet diradical (3OS) and
pure diradical (3T)
Table 2 Distribution of spin density, obtained by NBO analysis, in 3T (see Fig. 4 for atoms
labeling)
C atom
Spin density
1
2
3
4
5
6
7
8
9
10
11
12
0.230
0.250
0.320
0.290
0.290
0.329
0.271
0.273
0.285
0.111
0.120
0.121
Fig 5 SOMO (a), SOMO-1 (b), and spin density map (c) for 3T
Fig 6 -HOMO (a), -HOMO (b), -LUMO (c), and -LUMO (d) for 3OS
Results for diradical 4
Fig 7 Optimized geometries with indicated bond lengths (Ǻ) for 4 as singlet diradical (4OS) and
pure diradical (4T)
Table 3 Distribution of spin density, obtained by NBO analysis, in 4T (see Fig. 7 for atoms
labeling)
C atom
Spin density
1, 8
0.092
2, 7
0.282
3, 6
0.288
4, 5
0.542
9
0.236
Fig 8 SOMO (a), SOMO-1 (b), and spin density map (c) for 4T
Fig 9 -HOMO (a), -HOMO (b), -LUMO (c), and -LUMO (d) for 4OS
Discussion
In all examined diradicals the unpaired electrons are delocalized over almost the entire molecules.
This delocalization contributes to the stability of the diradical structures. The spin density maps are
in perfest agreement with the spin density values resulting from the NBO analysis.
Electronic structures of 2 and 4 are similar to that of 1. Namely, SOMO and SOMO-1 of 2T
and 4T, as well as  and β electrons of HOMO and LUMO of 2OS and 4OS occupy different parts
of space with small sharing region. The lower diradical character of 3 can be attributted to its larger
shearing region.