. 2021 Jul 3;7(7):e07461. doi: 10.1016/j.heliyon.2021.e07461

Table 2 (b).

Second-order perturbation theory of Fock matrix in NBO basis for $C_{8} H_{6} B_{2} S_{8}$ .

Donor (i)	type	occupancy	Acceptor (j)	type	Occupancy	E(2)^a kcal/mol	E_i-E_j^b a.u	F(i,j)^c a.u
C 1–C 2	σ	1.99035	C 1–S 8	σ∗	0.04326	1.37	1.00	0.033
C 1–C 2	σ	1.99035	C 1–S 12	σ∗	0.03860	0.65	0.98	0.023
C 1–C 2	σ	1.99035	C 2–S 7	σ∗	0.04323	1.37	1.00	0.033
C 1–C 2	σ	1.99035	C 2–S 11	σ∗	0.03822	0.65	0.98	0.023
C 1–C 2	π	1.91921	S 7–B 18	π∗	0.07744	1.86	0.32	0.022
C 1–C 2	π	1.91921	S 8–B 20	π∗	0.07744	1.86	0.32	0.022
C 1–S 8	σ	1.97668	C 1–C 2	σ∗	0.03939	3.41	1.27	0.059
C 1–S 8	σ	1.97668	C 2–S 11	σ∗	0.03822	3.79	0.86	0.051
C 1–S 8	σ	1.97668	C 3–S 12	σ∗	0.04381	0.61	0.86	0.021
C 1–S 8	σ	1.97668	B 20–H 21	σ∗	0.00834	0.88	1.19	0.029
C 1–S 12	σ	1.96758	C 1–C 2	σ∗	0.03939	2.01	1.24	0.045
C 1–S 12	σ	1.96758	C 2–S 7	σ∗	0.04323	6.16	0.85	0.065
C 1–S 12	σ	1.96758	C 3–C 6	σ∗	0.04510	2.27	1.26	0.048
C 1–S 12	σ	1.96758	C 3–C 6	π∗	0.37850	0.84	0.67	0.023
C 1–S 12	σ	1.96758	S 8–B 20	σ∗	0.01183	1.32	0.94	0.032
C 2–S 7	σ	1.97664	C 1–C 2	σ∗	0.03939	3.41	1.27	0.059
C 2–S 7	σ	1.97664	C 1–S 12	σ∗	0.03860	3.79	0.86	0.051
C 2–S 7	σ	1.97664	C 3–S 11	σ∗	0.04367	0.61	0.86	0.021
C 2–S 7	σ	1.97664	B 18–H 19	σ∗	0.00834	0.88	1.19	0.029
C 2–S 11	σ	1.96756	C 1–C 2	σ∗	0.03939	2.01	1.24	0.045
C 2–S 11	σ	1.96756	C 1–S 8	σ∗	0.04326	6.17	0.85	0.065
C 2–S 11	σ	1.96756	C 3–C 6	σ∗	0.04510	2.27	1.26	0.048
C 2–S 11	σ	1.96756	C 3–C 6	π∗	0.37850	0.83	0.67	0.023
C 2–S 11	σ	1.96756	S 7–B 18	σ∗	0.01182	1.32	0.94	0.032
C 3–C 6	σ	1.99004	C 3–S 11	σ∗	0.04367	0.97	0.97	0.028
C 3–C 6	σ	1.99004	C 3–S 12	σ∗	0.04381	0.98	0.97	0.028
C 3–C 6	σ	1.99004	C 6–S 13	σ∗	0.04607	0.92	0.97	0.027
C 3–C 6	σ	1.99004	C 6–S 14	σ∗	0.04433	0.92	0.97	0.027
C 3–C 6	π	1.96263	C 1–S 12	σ∗	0.03860	0.51	0.50	0.014
C 3–C 6	π	1.96263	C 2–S 11	σ∗	0.03822	0.52	0.50	0.014
C 3–C 6	π	1.96263	C 4–S 13	σ∗	0.04649	0.53	0.51	0.015
C 3–C 6	π	1.96263	C 5–S 14	σ∗	0.03888	0.58	0.51	0.015
C 3–S 12	σ	1.97028	C 1–S 8	σ∗	0.04326	2.80	0.85	0.044
C 3–S 12	σ	1.97028	C 3–C 6	σ∗	0.04510	2.15	1.27	0.047
C 3–S 12	σ	1.97028	C 6–S 13	σ∗	0.04607	5.47	0.84	0.061
C 4–C 5	σ	1.99019	C 4–S 9	σ∗	0.03132	1.35	1.00	0.033
C 4–C 5	σ	1.99019	C 4–S 13	σ∗	0.04649	0.74	0.98	0.024
C 4–C 5	σ	1.99019	C 5––S 10	σ∗	0.03441	1.17	0.99	0.030
C 4–C 5	σ	1.99019	C 5–S 14	σ∗	0.03888	0.74	0.98	0.024
C 4–C 5	π	1.96745	S 9–C 15	σ∗	0.02987	0.95	0.45	0.018
C 4–S 9	σ	1.97374	C 4–C 5	σ∗	0.03994	3.29	1.27	0.058
C 4–S 9	σ	1.97374	C 5–S 14	σ∗	0.03888	4.37	0.85	0.054
C 4–S 9	σ	1.97374	C 6–S 13	σ∗	0.04607	0.63	0.84	0.021
C 4–S 9	σ	1.97374	C 15–H 16	σ∗	0.00924	1.15	1.10	0.032
C 4–S 13	σ	1.96798	C 3–C 6	σ∗	0.04510	2.28	1.26	0.048
C 4–S 13	σ	1.96798	C 3–C 6	π∗	0.37850	0.92	0.66	0.024
C 4–S 13	σ	1.96798	C 4–C 5	σ∗	0.03994	2.08	1.25	0.046
C 4–S 13	σ	1.96798	C 5–S 10	σ∗	0.03441	5.97	0.84	0.063
C 4–S 13	σ	1.96798	S 9–C 15	σ∗	0.02987	0.67	0.79	0.021
C 5–S 10	σ	1.97317	C 4–C 5	σ∗	0.03994	3.06	1.27	0.056
C 5–S 10	σ	1.97317	C 4–S 13	σ∗	0.04649	4.42	0.85	0.055
C 5–S 10	σ	1.97317	C 6–S 14	σ∗	0.04433	0.60	0.84	0.020
C 5–S 10	σ	1.97317	S 10–C 22	σ∗	0.02157	0.62	0.85	0.020
C 5–S 10	σ	1.97317	C 22–H 23	σ∗	0.01928	0.72	1.14	0.026
C 5–S 10	σ	1.97317	C 22–H 24	σ∗	0.01944	0.75	1.14	0.026
C 5–S 14	σ	1.96806	C 3–C 6	σ∗	0.04510	2.25	1.26	0.048
C 5–S 14	σ	1.96806	C 3–C 6	π∗	0.37850	0.93	0.66	0.024
C 5–S 14	σ	1.96806	C 4–C 5	σ∗	0.03994	2.04	1.26	0.045
C 5–S 14	σ	1.96806	C 4–S 9	σ∗	0.03132	5.83	0.85	0.063
C 5–S 14	σ	1.96806	S 10–C 22	σ∗	0.02157	0.98	0.83	0.026
C 6–S 13	σ	1.96893	C 3–C 6	σ∗	0.04510	2.14	1.26	0.046
C 6–S 13	σ	1.96893	C 3–S 12	σ∗	0.04381	5.71	0.83	0.062
C 6–S 13	σ	1.96893	C 4–S 9	σ∗	0.03132	3.11	0.85	0.046
C 6–S 14	σ	1.96896	C 3–C 6	σ∗	0.04510	2.10	1.26	0.046
C 6–S 14	σ	1.96896	C 3–S 11	σ∗	0.04367	5.66	0.83	0.061
C 6–S 14	σ	1.96896	C 5–S 10	σ∗	0.03441	3.12	0.84	0.046
S 7–B 18	σ	1.98208	C 2–S 11	σ∗	0.03822	3.03	0.83	0.045
S 7–B 18	σ	1.98208	B 20–H 21	σ∗	0.00834	1.59	1.17	0.039
S 7–B 18	π	1.87086	C 1–C 2	π∗	0.36429	15.50	0.27	0.061
S 7–B 18	π	1.87086	S 7–B 18	π∗	0.07744	0.61	0.29	0.012
S 7–B 18	π	1.87086	S 8–B 20	π∗	0.07744	4.42	0.29	0.032
S 8–B 20	σ	1.98208	C 1–S 12	σ∗	0.03860	3.03	0.83	0.045
S 8–B 20	σ	1.98208	B 18–H 19	σ∗	0.00834	1.59	1.17	0.039
S 8–B 20	π	1.87085	C 1–C 2	π∗	0.36429	15.50	0.27	0.061
S 8–B 20	π	1.87085	S 7–B 18	π∗	0.07744	4.42	0.29	0.032
S 8–B 20	π	1.87085	S 8–B 20	π∗	0.07744	0.61	0.29	0.012
S 9–C 15	σ	1.97492	C 4–C 5	π∗	0.37201	1.43	0.58	0.028
S 9–C 15	σ	1.97492	C 4–S 13	σ∗	0.04649	2.27	0.77	0.038
S 9–C 15	σ	1.97492	C 22–H 23	σ∗	0.01928	1.81	1.07	0.039
C 15–H 16	σ	1.97682	C 4–S 9	σ∗	0.03132	1.61	0.73	0.031
C 15–H 16	σ	1.97682	S 10–C 22	σ∗	0.02157	4.31	0.71	0.049
C 15–H 17	σ	1.99014	C 22–H 24	σ∗	0.01944	1.39	1.00	0.033
B 18–H 19	σ	1.96961	C 2–S 7	σ∗	0.04323	3.95	0.60	0.044
B 18–H 19	σ	1.96961	S 8–B 20	σ∗	0.01183	2.78	0.69	0.039
B 20–H 21	σ	1.96962	C 1–S 8	σ∗	0.04326	3.95	0.60	0.044
B 20–H 21	σ	1.96962	S 7–B 18	σ∗	0.01182	2.78	0.69	0.039
C 22–H 23	σ	1.97504	C 5–S 10	σ∗	0.03441	1.02	0.72	0.024
C 22–H 23	σ	1.97504	S 9–C 15	σ∗	0.02987	4.32	0.67	0.048
C 22–H 24	σ	1.98241	C 5–S 10	σ∗	0.03441	0.68	0.71	0.020
C 22–H 24	σ	1.98241	C 15–H 17	σ∗	0.02207	3.59	0.96	0.052
S 7	LP (1)	1.96802	C 1–C 2	σ∗	0.03939	6.92	1.17	0.080
S 7	LP (1)	1.96802	B 18–H 19	σ∗	0.00834	0.57	1.09	0.022
S 7	LP (1)	1.96802	B 18–B 20	σ∗	0.01339	3.01	1.04	0.050
S 8	LP (1)	1.96802	C 1–C 2	σ∗	0.03939	6.92	1.17	0.080
S 8	LP (1)	1.96802	B 18–B 20	σ∗	0.01339	3.01	1.04	0.050
S 8	LP (1)	1.96802	B 20–H 21	σ∗	0.00834	0.57	1.09	0.022
S 9	LP (1)	1.97732	C 4–C 5	σ∗	0.03994	4.74	1.24	0.069
S 9	LP (1)	1.97732	C 15–H 17	σ∗	0.02207	0.62	1.07	0.023
S 9	LP (1)	1.97732	C 15–C 22	σ∗	0.02966	1.19	0.94	0.030
S 9	LP (2)	1.97732	C 4–C 5	σ∗	0.03994	1.73	0.85	0.035
S 9	LP (2)	1.97732	C 4–C 5	π∗	0.37201	12.98	0.23	0.052
S 9	LP (2)	1.97732	C 4–S 13	σ∗	0.04649	3.25	0.43	0.034
S 9	LP (2)	1.97732	C 6–S 13	σ∗	0.04607	0.52	0.42	0.013
S 9	LP (2)	1.97732	C 15–H 17	σ∗	0.02207	4.03	0.68	0.048
S 9	LP (2)	1.97732	C 15–C 22	σ∗	0.02966	3.16	0.55	0.038
S 9	LP (2)	1.97732	C 22–H 23	σ∗	0.01928	0.82	0.72	0.022
S 10	LP (1)	1.97275	C 4–C 5	σ∗	0.03994	5.00	1.22	0.070
S 10	LP (1)	1.97275	C 15–C 22	σ∗	0.02966	4.23	0.92	0.056
S 10	LP (2)	1.97275	C 4–C 5	σ∗	0.03994	0.58	0.85	0.020
S 10	LP (2)	1.97275	C 4–C 5	π∗	0.37201	18.38	0.24	0.063
S 10	LP (2)	1.97275	C 5–S 14	σ∗	0.03888	1.21	0.42	0.021
S 10	LP (2)	1.97275	C 22–H 23	σ∗	0.01928	3.22	0.72	0.045
S 10	LP (2)	1.97275	C 22–H 24	σ∗	0.01944	4.60	0.72	0.053
S 11	LP (1)	1.97208	C 1–C 2	σ∗	0.03939	3.10	1.24	0.056
S 11	LP (1)	1.97208	C 3–S 12	σ∗	0.04381	3.47	0.83	0.048
S 11	LP (2)	1.78173	C 1–C 2	π∗	0.36429	20.69	0.23	0.064
S 11	LP (2)	1.78173	C 3–C 6	σ∗	0.04510	1.20	0.85	0.030
S 11	LP (2)	1.78173	C 3–C 6	π∗	0.37850	14.76	0.26	0.058
S 11	LP (2)	1.78173	C 3–S 12	σ∗	0.04381	0.82	0.42	0.017
S 12	LP (1)	1.97207	C 1–C 2	σ∗	0.03939	3.10	1.24	0.056
S 12	LP (1)	1.97207	C 3–S 11	σ∗	0.04367	3.48	0.83	0.048
S 12	LP (2)	1.78199	C 1–C 2	π∗	0.36429	20.68	0.23	0.064
S 12	LP (2)	1.78199	C 3–C 6	σ∗	0.04510	1.19	0.85	0.030
S 12	LP (2)	1.78199	C 3–C 6	π∗	0.37850	14.79	0.26	0.058
S 12	LP (2)	1.78199	C 3–S 11	σ∗	0.04367	0.81	0.42	0.017
S 13	LP (1)	1.97220	C 4–C 5	σ∗	0.03994	3.04	1.25	0.055
S 13	LP (1)	1.97220	C 6–S 14	σ∗	0.04433	3.39	0.83	0.047
S 13	LP (2)	1.78677	C 3–C 6	σ∗	0.04510	1.32	0.85	0.031
S 13	LP (2)	1.78677	C 3–C 6	π∗	0.37850	14.53	0.25	0.057
S 13	LP (2)	1.78677	C 4–C 5	π∗	0.37201	19.94	0.23	0.064
S 13	LP (2)	1.78677	C 6–S 14	σ∗	0.04433	1.06	0.42	0.020
S 14	LP (1)	1.97266	C 4–C 5	σ∗	0.03994	3.02	1.26	0.055
S 14	LP (1)	1.97266	C 6–S 13	σ∗	0.04607	3.34	0.83	0.047
S 14	LP (2)	1.78820	C 3–C 6	σ∗	0.04510	1.39	0.85	0.032
S 14	LP (2)	1.78820	C 3–C 6	π∗	0.37850	14.23	0.26	0.056
S 14	LP (2)	1.78820	C 4–C 5	π∗	0.37201	19.44	0.24	0.063
S 14	LP (2)	1.78820	C 6–S 13	σ∗	0.04607	1.08	0.42	0.020

E(2) means energy of hyper conjugative interaction (stabilization energy).

Energy difference between donor and acceptor i and j NBO orbitals.

F(i,j) is the Fock matrix element between i and j NBO orbitals.