CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	TD	¹A₁

Energy calculated at QCISD/3-21G*

	hartrees
Energy at 0K	-445.649908
Energy at 298.15K	-445.661427
HF Energy	-445.136633
Nuclear repulsion energy	243.798418

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at QCISD/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	2990	2873	0.00
2	A₁	1397	1342	0.00
3	A₁	592	569	0.00
4	A₂	154	148	0.00
5	E	3056	2937	0.00
5	E	3056	2937	0.00
6	E	1537	1477	0.00
6	E	1537	1477	0.00
7	E	895	860	0.00
7	E	895	860	0.00
8	E	189	181	0.00
8	E	189	181	0.00
9	T₁	3056	2937	0.00
9	T₁	3056	2937	0.00
9	T₁	3056	2937	0.00
10	T₁	1533	1474	0.00
10	T₁	1533	1474	0.00
10	T₁	1533	1474	0.00
11	T₁	744	715	0.00
11	T₁	744	715	0.00
11	T₁	744	715	0.00
12	T₁	171	165	0.00
12	T₁	171	165	0.00
12	T₁	171	165	0.00
13	T₂	3060	2940	49.81
13	T₂	3060	2940	49.81
13	T₂	3060	2940	49.81
14	T₂	2989	2872	9.53
14	T₂	2989	2872	9.53
14	T₂	2989	2872	9.53
15	T₂	1552	1491	6.02
15	T₂	1552	1491	6.02
15	T₂	1552	1491	6.02
16	T₂	1387	1334	39.20
16	T₂	1387	1334	39.20
16	T₂	1387	1334	39.20
17	T₂	956	919	142.32
17	T₂	956	919	142.32
17	T₂	956	919	142.32
18	T₂	718	690	14.02
18	T₂	718	690	14.02
18	T₂	718	690	14.02
19	T₂	227	218	2.85
19	T₂	227	218	2.85
19	T₂	227	218	2.85

Unscaled Zero Point Vibrational Energy (zpe) 32831.5 cm^-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 31554.3 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at QCISD/3-21G*

A	B	C
0.10147	0.10147	0.10147

See section I.F.4 to change rotational constant units

Geometric Data calculated at QCISD/3-21G*

Point Group is T_d

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	0.000
C2	1.095	1.095	1.095
C3	-1.095	-1.095	1.095
C4	-1.095	1.095	-1.095
C5	1.095	-1.095	-1.095
H6	1.745	0.484	1.745
H7	1.745	1.745	0.484
H8	0.484	1.745	1.745
H9	-1.745	-1.745	0.484
H10	-0.484	-1.745	1.745
H11	-1.745	-0.484	1.745
H12	-1.745	0.484	-1.745
H13	-1.745	1.745	-0.484
H14	-0.484	1.745	-1.745
H15	1.745	-1.745	-0.484
H16	0.484	-1.745	-1.745
H17	1.745	-0.484	-1.745

Atom - Atom Distances (Å)

	Si1	C2	C3	C4	C5	H6	H7	H8	H9	H10	H11	H12	H13	H14	H15	H16	H17
Si1		1.8971	1.8971	1.8971	1.8971	2.5145	2.5145	2.5145	2.5145	2.5145	2.5145	2.5145	2.5145	2.5145	2.5145	2.5145	2.5145
C2	1.8971		3.0979	3.0979	3.0979	1.1031	1.1031	1.1031	4.0626	3.3140	3.3140	4.0626	3.3140	3.3140	3.3140	4.0626	3.3140
C3	1.8971	3.0979		3.0979	3.0979	3.3140	4.0626	3.3140	1.1031	1.1031	1.1031	3.3140	3.3140	4.0626	3.3140	3.3140	4.0626
C4	1.8971	3.0979	3.0979		3.0979	4.0626	3.3140	3.3140	3.3140	4.0626	3.3140	1.1031	1.1031	1.1031	4.0626	3.3140	3.3140
C5	1.8971	3.0979	3.0979	3.0979		3.3140	3.3140	4.0626	3.3140	3.3140	4.0626	3.3140	4.0626	3.3140	1.1031	1.1031	1.1031
H6	2.5145	1.1031	3.3140	4.0626	3.3140		1.7825	1.7825	4.3282	3.1523	3.6214	4.9348	4.3282	4.3282	3.1523	4.3282	3.6214
H7	2.5145	1.1031	4.0626	3.3140	3.3140	1.7825		1.7825	4.9348	4.3282	4.3282	4.3282	3.6214	3.1523	3.6214	4.3282	3.1523
H8	2.5145	1.1031	3.3140	3.3140	4.0626	1.7825	1.7825		4.3282	3.6214	3.1523	4.3282	3.1523	3.6214	4.3282	4.9348	4.3282
H9	2.5145	4.0626	1.1031	3.3140	3.3140	4.3282	4.9348	4.3282		1.7825	1.7825	3.1523	3.6214	4.3282	3.6214	3.1523	4.3282
H10	2.5145	3.3140	1.1031	4.0626	3.3140	3.1523	4.3282	3.6214	1.7825		1.7825	4.3282	4.3282	4.9348	3.1523	3.6214	4.3282
H11	2.5145	3.3140	1.1031	3.3140	4.0626	3.6214	4.3282	3.1523	1.7825	1.7825		3.6214	3.1523	4.3282	4.3282	4.3282	4.9348
H12	2.5145	4.0626	3.3140	1.1031	3.3140	4.9348	4.3282	4.3282	3.1523	4.3282	3.6214		1.7825	1.7825	4.3282	3.1523	3.6214
H13	2.5145	3.3140	3.3140	1.1031	4.0626	4.3282	3.6214	3.1523	3.6214	4.3282	3.1523	1.7825		1.7825	4.9348	4.3282	4.3282
H14	2.5145	3.3140	4.0626	1.1031	3.3140	4.3282	3.1523	3.6214	4.3282	4.9348	4.3282	1.7825	1.7825		4.3282	3.6214	3.1523
H15	2.5145	3.3140	3.3140	4.0626	1.1031	3.1523	3.6214	4.3282	3.6214	3.1523	4.3282	4.3282	4.9348	4.3282		1.7825	1.7825
H16	2.5145	4.0626	3.3140	3.3140	1.1031	4.3282	4.3282	4.9348	3.1523	3.6214	4.3282	3.1523	4.3282	3.6214	1.7825		1.7825
H17	2.5145	3.3140	4.0626	3.3140	1.1031	3.6214	3.1523	4.3282	4.3282	4.3282	4.9348	3.6214	4.3282	3.1523	1.7825	1.7825

picture of tetramethylsilane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
Si1	C2	H6	111.102	Si1	C2	H7	111.102
Si1	C2	H8	111.102	Si1	C3	H9	111.102
Si1	C3	H10	111.102	Si1	C3	H11	111.102
Si1	C4	H12	111.102	Si1	C4	H13	111.102
Si1	C4	H14	111.102	Si1	C5	H15	111.102
Si1	C5	H16	111.102	Si1	C5	H17	111.102
C2	Si1	C3	109.471	C2	Si1	C4	109.471
C2	Si1	C5	109.471	C3	Si1	C4	109.471
C3	Si1	C5	109.471	C4	Si1	C5	109.471
H6	C2	H7	107.792	H6	C2	H8	107.792
H7	C2	H8	107.792	H9	C3	H10	107.792
H9	C3	H11	107.792	H10	C3	H11	107.792
H12	C4	H13	107.792	H12	C4	H14	107.792
H13	C4	H14	107.792	H15	C5	H16	107.792
H15	C5	H17	107.792	H16	C5	H17	107.792

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for Si(CH₃)₄ (tetramethylsilane)

using model chemistry: QCISD/3-21G*

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All results from a given calculation for Si(CH3)4 (tetramethylsilane)

using model chemistry: QCISD/3-21G*

States and conformations

All results from a given calculation for Si(CH₃)₄ (tetramethylsilane)