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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	-579.001184
Energy at 298.15K
HF Energy	-578.822502
Nuclear repulsion energy	67.131703

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	2403	2225	0.00
2	Σ_g	777	719	0.00
3	Σ_u	2397	2220	5.48
4	Π_g	607i	562i	0.00
4	Π_g	607i	562i	0.00
5	Π_u	425	394	1.68
5	Π_u	425	394	1.68

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	0.986
Si2	0.000	0.000	-0.986
H3	0.000	0.000	2.451
H4	0.000	0.000	-2.451

	Si1	Si2	H3	H4
Si1		1.9717	1.4656	3.4373
Si2	1.9717		3.4373	1.4656
H3	1.4656	3.4373		4.9029
H4	3.4373	1.4656	4.9029

All results from a given calculation for Si₂H₂ (disilyne)

using model chemistry: CISD/6-31G*

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	-579.034595
Energy at 298.15K
HF Energy	-578.849348
Nuclear repulsion energy	64.010370

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	2260	2092	0.00
2	A_g	637	590	0.00
3	A_g	583	540	0.00
4	A_u	541	501	1.31
5	B_u	2263	2095	185.98
6	B_u	330	306	42.48

Atom	x (Å)	y (Å)
Si1	0.000	1.051
Si2	0.000	-1.051
H3	1.227	1.902
H4	-1.227	-1.902

	Si1	Si2	H3	H4
Si1		2.1024	1.4927	3.1976
Si2	2.1024		3.1976	1.4927
H3	1.4927	3.1976		4.5261
H4	3.1976	1.4927	4.5261

	hartrees
Energy at 0K	-579.061275
Energy at 298.15K
HF Energy	-578.885302
Nuclear repulsion energy	65.165117

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	1698	1572	12.70
2	A₁	1010	935	63.95
3	A₁	564	522	1.34
4	A₂	1105	1023	0.00
5	B₁	1607	1488	40.37
6	B₂	1217	1126	452.10

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	1.099	-0.052
Si2	0.000	-1.099	-0.052
H3	0.993	0.000	0.729
H4	-0.993	0.000	0.729

	Si1	Si2	H3	H4
Si1		2.1974	1.6745	1.6745
Si2	2.1974		1.6745	1.6745
H3	1.6745	1.6745		1.9862
H4	1.6745	1.6745	1.9862

	hartrees
Energy at 0K	-579.045158
Energy at 298.15K
HF Energy	-578.865033
Nuclear repulsion energy	65.243006

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A'	2268	2100	102.86
2	A'	1719	1592	118.14
3	A'	1083	1003	174.43
4	A'	635	588	20.91
5	A'	451	418	9.37
6	A"	52	49	47.72

	Si1	Si2	H3	H4
Si1		2.1092	1.7394	3.5487
Si2	2.1092		1.6332	1.4894
H3	1.7394	1.6332		2.5122
H4	3.5487	1.4894	2.5122

Atom	x (Å)	y (Å)
Si1	0.060	-1.139
Si2	0.060	0.970
H3	-1.254	0.000
H4	-0.434	2.375

All results from a given calculation for Si2H2 (disilyne)

using model chemistry: CISD/6-31G*

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)