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State	Conformation	minimum conformation	conformer description	state description
1	1	no	D*H	¹Σ_G
1	2	no	C2H	¹A_G
1	3	yes	C2V	¹A₁
1	4	no	CS	¹A^'

	hartrees
Energy at 0K	-8.553997
Energy at 298.15K
HF Energy	-8.438871
Nuclear repulsion energy	8.237703

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	2272	2195	0.00	382.94	0.60	0.75
2	Σ_g	683	660	0.00	38.79	0.33	0.49
3	Σ_u	2266	2190	0.48	0.00	0.00	0.00
4	Π_g	601i	580i	0.00	92.11	0.75	0.86
4	Π_g	601i	580i	0.00	92.11	0.75	0.86
5	Π_u	379	367	10.42	0.00	0.00	0.00
5	Π_u	379	367	10.42	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	1.036
Si2	0.000	0.000	-1.036
H3	0.000	0.000	2.519
H4	0.000	0.000	-2.519

	Si1	Si2	H3	H4
Si1		2.0716	1.4830	3.5546
Si2	2.0716		3.5546	1.4830
H3	1.4830	3.5546		5.0376
H4	3.5546	1.4830	5.0376

All results from a given calculation for Si₂H₂ (disilyne)

using model chemistry: MP2/CEP-31G

States and conformations

Conformer 1 (D*H)

Conformer 2 (C2H)

Conformer 3 (C2V)

Conformer 4 (CS)

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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You are here: Calculated > Energy > Optimized > Energy

	hartrees
Energy at 0K	-8.586776
Energy at 298.15K
HF Energy	-8.472824
Nuclear repulsion energy	8.064858

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	A_g	2102	2031	0.00	790.28	0.27	0.43
2	A_g	614	593	0.00	2172.59	0.37	0.54
3	A_g	576	557	0.00	3496.78	0.41	0.58
4	A_u	914	884	906.36	0.00	0.00	0.00
5	B_u	2119	2048	267.69	0.00	0.00	0.00
6	B_u	562	543	71.75	0.00	0.00	0.00

Atom	x (Å)	y (Å)
Si1	0.000	1.087
Si2	0.000	-1.087
H3	1.235	1.981
H4	-1.235	-1.981

	Si1	Si2	H3	H4
Si1		2.1746	1.5240	3.3070
Si2	2.1746		3.3070	1.5240
H3	1.5240	3.3070		4.6679
H4	3.3070	1.5240	4.6679

	hartrees
Energy at 0K	-8.590167
Energy at 298.15K
HF Energy	-8.491564
Nuclear repulsion energy	8.588376

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	A₁	1509	1458	26.03	121.56	0.06	0.12
2	A₁	905	874	108.25	37.32	0.24	0.38
3	A₁	421	407	7.08	37.76	0.57	0.72
4	A₂	970	937	0.00	5.03	0.75	0.86
5	B₁	1396	1349	75.81	81.12	0.75	0.86
6	B₂	1064	1028	544.11	1.60	0.75	0.86

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	1.192	-0.053
Si2	0.000	-1.192	-0.053
H3	1.035	0.000	0.747
H4	-1.035	0.000	0.747

	Si1	Si2	H3	H4
Si1		2.3848	1.7704	1.7704
Si2	2.3848		1.7704	1.7704
H3	1.7704	1.7704		2.0710
H4	1.7704	1.7704	2.0710

	hartrees
Energy at 0K	-8.586422
Energy at 298.15K
HF Energy	-8.479840
Nuclear repulsion energy	8.303203

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	A'	2104	2033	150.32	396.29	0.54	0.70
2	A'	1541	1489	120.10	185.05	0.34	0.51
3	A'	922	891	282.36	6.82	0.71	0.83
4	A'	557	538	35.09	12.32	0.70	0.83
5	A'	422	408	24.79	0.94	0.58	0.74
6	A"	240	232	59.07	4.06	0.75	0.86

	Si1	Si2	H3	H4
Si1		2.2430	1.8893	3.7311
Si2	2.2430		1.6990	1.5182
H3	1.8893	1.6990		2.6371
H4	3.7311	1.5182	2.6371

Atom	x (Å)	y (Å)
Si1	0.059	-1.213
Si2	0.059	1.030
H3	-1.336	0.061
H4	-0.329	2.498

All results from a given calculation for Si2H2 (disilyne)

using model chemistry: MP2/CEP-31G

States and conformations

Conformer 1 (D*H)

Conformer 2 (C2H)

Conformer 3 (C2V)

Conformer 4 (CS)

All results from a given calculation for Si₂H₂ (disilyne)