Table 1.

Structural and optical properties calculated for isomers varying from Si₁₅ to Si₂₀

Isomer	E (au)	rel. E (eV)	Band gap (eV)	Dipole (Debye)	D (nm)	Polarizability/atom	ZPE (eV)	Ovality	UV-VIS lambda max
15A	−4,342.34404	0.00	3.051	3.097	0.72508	4.629	0.632	1.2115	525.314
15B	−4,342.32497	0.52	1.889	0.959	0.72991	4.648	0.629	1.2035	871.635
15C	−4,342.31698	0.74	1.971	0.525	0.72724	4.656	0.614	1.2099	750.415
15D	−4,342.30761	0.99	3.441	0.027	0.75043	4.594	0.589	1.1645	431.109
16A	−4,631.80268	0.18	1.954	0.00	0.75701	4.465	0.636	1.1833	750.886
16B	−4,631.80953	0.00	2.450	0.54	0.73474	4.456	0.663	1.2189	583.651
16C	−4,631.79720	0.33	2.250	0.76	0.75324	4.469	0.625	1.1911	630.165
17A	−4,921.27172	0.8	1.053	2.384	0.70364	4.356	0.706	1.2540	1,033.850
17B	−4,920.97362	8.659a	0.619	0.180	0.76368	4.494	0.886	1.4320	2,747.970
17C	−4,921.30164	0.00	1.874	0.638	0.75456	4.311	0.757	1.2104	838.4698
18A	−5,210.83526	0.00	2.255	2.84	0.74512	4.177	0.80	1.2504	552.447
18B	−5,210.80158	0.92	1.388	0.04	0.73920	4.178	0.74	1.2580	692.813
18C	−5,210.80010	0.96	1.323	0.01	0.73906	4.178	0.73	1.2581	1,732.74
18D	Not converged
19A	−5,500.25750	1.98	1.878	3.45	0.7361	4.098	0.81	1.2965	700.980
19B	−5,500.33041	0.00	2.198	1.93	0.7544	4.058	0.83	1.2571	643.427
19C	−5,500.28806	1.15	2.351	1.21	0.7259	4.076	0.82	1.3112	678.640
20A	−5,789.84528	0.00	2.7320	1.54	0.74238	3.9476	0.92	1.3005	549.724
20B	−5,789.81937	0.71	2.9045	0.00	0.75361	3.9465	0.87	1.2813	540.264
20C	−5,789.76867	2.08	1.6437	0.73	0.77313	3.9727	0.90	1.2514	756.136

^aIsomer Si17B presents and unexpected energy.