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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	-579.019823
Energy at 298.15K
HF Energy	-578.821510
Nuclear repulsion energy	66.617737

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	2351	2220	0.00
2	Σ_g	741	700	0.00
3	Σ_u	2347	2216	4.74
4	Π_g	631i	595i	0.00
4	Π_g	631i	595i	0.00
5	Π_u	373	353	3.53
5	Π_u	373	353	3.53

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	2.466
H4	0.000	0.000	-2.466

	Si1	Si2	H3	H4
Si1		1.9884	1.4719	3.4603
Si2	1.9884		3.4603	1.4719
H3	1.4719	3.4603		4.9322
H4	3.4603	1.4719	4.9322

All results from a given calculation for Si₂H₂ (disilyne)

using model chemistry: CCSD/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	-579.055697
Energy at 298.15K
HF Energy	-578.848957
Nuclear repulsion energy	63.608467

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	2213	2090	0.00
2	A_g	627	592	0.00
3	A_g	576	544	0.00
4	A_u	363	342	26.36
5	B_u	2218	2094	167.25
6	B_u	316	298	29.90

Atom	x (Å)	y (Å)
Si1	0.000	1.059
Si2	0.000	-1.059
H3	1.242	1.897
H4	-1.242	-1.897

	Si1	Si2	H3	H4
Si1		2.1174	1.4986	3.2061
Si2	2.1174		3.2061	1.4986
H3	1.4986	3.2061		4.5350
H4	3.2061	1.4986	4.5350

	hartrees
Energy at 0K	-579.077403
Energy at 298.15K
HF Energy	-578.885168
Nuclear repulsion energy	64.948349

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	1677	1584	10.75
2	A₁	985	930	56.05
3	A₁	547	517	1.54
4	A₂	1109	1047	0.00
5	B₁	1585	1497	36.85
6	B₂	1210	1142	423.60

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	1.103	-0.052
Si2	0.000	-1.103	-0.052
H3	0.996	0.000	0.725
H4	-0.996	0.000	0.725

	Si1	Si2	H3	H4
Si1		2.2062	1.6771	1.6771
Si2	2.2062		1.6771	1.6771
H3	1.6771	1.6771		1.9926
H4	1.6771	1.6771	1.9926

	hartrees
Energy at 0K	-579.062899
Energy at 298.15K
HF Energy	-578.864488
Nuclear repulsion energy	64.886889

	Si1	Si2	H3	H4
Si1		2.1225	1.7386	3.5614
Si2	2.1225		1.6399	1.4967
H3	1.7386	1.6399		2.5065
H4	3.5614	1.4967	2.5065

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A'	2213	2090	101.86
2	A'	1686	1592	105.32
3	A'	1085	1025	166.69
4	A'	616	581	16.45
5	A'	448	423	7.84
6	A"	19	18	42.18

Atom	x (Å)	y (Å)
Si1	0.061	-1.146
Si2	0.061	0.977
H3	-1.251	-0.006
H4	-0.470	2.376

All results from a given calculation for Si2H2 (disilyne)

using model chemistry: CCSD/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)