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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	-579.142789
Energy at 298.15K
HF Energy	-578.881836
Nuclear repulsion energy	66.927210

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	2361	2222	0.00
2	Σ_g	757	712	0.00
3	Σ_u	2357	2219	0.01
4	Π_g	617i	581i	0.00
4	Π_g	617i	581i	0.00
5	Π_u	429	403	4.32
5	Π_u	429	403	4.32

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	0.990
Si2	0.000	0.000	-0.990
H3	0.000	0.000	2.452
H4	0.000	0.000	-2.452

	Si1	Si2	H3	H4
Si1		1.9803	1.4614	3.4417
Si2	1.9803		3.4417	1.4614
H3	1.4614	3.4417		4.9030
H4	3.4417	1.4614	4.9030

All results from a given calculation for Si₂H₂ (disilyne)

using model chemistry: CCSD/cc-pVTZ

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	-579.175216
Energy at 298.15K
HF Energy	-578.907633
Nuclear repulsion energy	63.845990

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	2211	2081	0.00
2	A_g	620	584	0.00
3	A_g	566	533	0.00
4	A_u	278	262	38.27
5	B_u	2215	2085	124.78
6	B_u	273	257	37.99

Atom	x (Å)	y (Å)
Si1	0.000	1.055
Si2	0.000	-1.055
H3	1.212	1.920
H4	-1.212	-1.920

	Si1	Si2	H3	H4
Si1		2.1095	1.4893	3.2121
Si2	2.1095		3.2121	1.4893
H3	1.4893	3.2121		4.5410
H4	3.2121	1.4893	4.5410

	hartrees
Energy at 0K	-579.207934
Energy at 298.15K
HF Energy	-578.950290
Nuclear repulsion energy	64.808150

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	1643	1546	2.89
2	A₁	936	881	32.07
3	A₁	541	509	0.69
4	A₂	1120	1054	0.00
5	B₁	1564	1472	13.12
6	B₂	1214	1143	412.04

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	1.107	-0.052
Si2	0.000	-1.107	-0.052
H3	0.990	0.000	0.723
H4	-0.990	0.000	0.723

	Si1	Si2	H3	H4
Si1		2.2139	1.6750	1.6750
Si2	2.2139		1.6750	1.6750
H3	1.6750	1.6750		1.9806
H4	1.6750	1.6750	1.9806

	hartrees
Energy at 0K	-579.189833
Energy at 298.15K
HF Energy	-578.928082
Nuclear repulsion energy	65.046194

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A'	2218	2088	82.17
2	A'	1670	1572	58.73
3	A'	1127	1061	136.75
4	A'	625	588	17.22
5	A'	460	433	5.11
6	A"	132	124	37.09

	Si1	Si2	H3	H4
Si1		2.1195	1.7209	3.5532
Si2	2.1195		1.6365	1.4868
H3	1.7209	1.6365		2.5180
H4	3.5532	1.4868	2.5180

Atom	x (Å)	y (Å)
Si1	0.060	-1.144
Si2	0.060	0.976
H3	-1.241	-0.017
H4	-0.448	2.373

All results from a given calculation for Si2H2 (disilyne)

using model chemistry: CCSD/cc-pVTZ

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)