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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	-579.036362
Energy at 298.15K
HF Energy	-578.826258
Nuclear repulsion energy	66.758882

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	2388	2230	0.00
2	Σ_g	742	693	0.00
3	Σ_u	2386	2228	4.05
4	Π_g	669i	624i	0.00
4	Π_g	669i	624i	0.00
5	Π_u	363	339	3.51
5	Π_u	363	339	3.51

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	0.994
Si2	0.000	0.000	-0.994
H3	0.000	0.000	2.451
H4	0.000	0.000	-2.451

	Si1	Si2	H3	H4
Si1		1.9876	1.4572	3.4449
Si2	1.9876		3.4449	1.4572
H3	1.4572	3.4449		4.9021
H4	3.4449	1.4572	4.9021

All results from a given calculation for Si₂H₂ (disilyne)

using model chemistry: CCSD/6-31+G**

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	-579.073415
Energy at 298.15K
HF Energy	-578.853405
Nuclear repulsion energy	63.718432

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	2251	2102	0.00
2	A_g	636	594	0.00
3	A_g	573	536	0.00
4	A_u	363	339	25.76
5	B_u	2256	2106	178.65
6	B_u	319	298	27.60

Atom	x (Å)	y (Å)
Si1	0.000	1.059
Si2	0.000	-1.059
H3	1.233	1.885
H4	-1.233	-1.885

	Si1	Si2	H3	H4
Si1		2.1180	1.4835	3.1913
Si2	2.1180		3.1913	1.4835
H3	1.4835	3.1913		4.5038
H4	3.1913	1.4835	4.5038

	hartrees
Energy at 0K	-579.101531
Energy at 298.15K
HF Energy	-578.892797
Nuclear repulsion energy	65.095720

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	1722	1608	8.56
2	A₁	990	925	57.88
3	A₁	544	508	1.34
4	A₂	1165	1088	0.00
5	B₁	1624	1516	19.56
6	B₂	1262	1179	453.29

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	1.104	-0.051
Si2	0.000	-1.104	-0.051
H3	0.982	0.000	0.708
H4	-0.982	0.000	0.708

	Si1	Si2	H3	H4
Si1		2.2077	1.6605	1.6605
Si2	2.2077		1.6605	1.6605
H3	1.6605	1.6605		1.9635
H4	1.6605	1.6605	1.9635

	hartrees
Energy at 0K	-579.083302
Energy at 298.15K
HF Energy	-578.870397
Nuclear repulsion energy	65.041779

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A'	2252	2103	110.72
2	A'	1726	1612	101.42
3	A'	1166	1089	175.35
4	A'	618	577	15.47
5	A'	467	436	5.74
6	A"	83i	77i	50.47

	Si1	Si2	H3	H4
Si1		2.1232	1.7104	3.5403
Si2	2.1232		1.6268	1.4814
H3	1.7104	1.6268		2.4791
H4	3.5403	1.4814	2.4791

Atom	x (Å)	y (Å)
Si1	0.061	-1.145
Si2	0.061	0.978
H3	-1.225	-0.018
H4	-0.495	2.351

All results from a given calculation for Si2H2 (disilyne)

using model chemistry: CCSD/6-31+G**

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)