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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

	hartrees
Energy at 0K	-578.779765
Energy at 298.15K
HF Energy	-578.779765
Nuclear repulsion energy	67.037553

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	2458	2213	0.00	227.32	0.35	0.51
2	Σ_g	800	721	0.00	87.24	0.32	0.49
3	Σ_u	2451	2207	2.37	0.00	0.00	0.00
4	Π_g	600i	540i	0.00	114.21	0.75	0.86
4	Π_g	600i	540i	0.00	114.21	0.75	0.86
5	Π_u	488	440	0.82	0.00	0.00	0.00
5	Π_u	488	440	0.82	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	0.989
Si2	0.000	0.000	-0.989
H3	0.000	0.000	2.442
H4	0.000	0.000	-2.442

	Si1	Si2	H3	H4
Si1		1.9790	1.4524	3.4314
Si2	1.9790		3.4314	1.4524
H3	1.4524	3.4314		4.8839
H4	3.4314	1.4524	4.8839

All results from a given calculation for Si₂H₂ (disilyne)

using model chemistry: HF/SDD

States and conformations

Conformer 1 (D*H)

Conformer 2 (C2H)

Conformer 3 (C2V)

	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	-578.808322
Energy at 298.15K
HF Energy	-578.808322
Nuclear repulsion energy	63.509752

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	2275	2048	0.00	398.76	0.51	0.68
2	A_g	653	588	0.00	140.35	0.43	0.60
3	A_g	530	477	0.00	302.05	0.08	0.15
4	A_u	307i	276i	353.79	0.00	0.00	0.00
5	B_u	2279	2052	209.52	0.00	0.00	0.00
6	B_u	51i	46i	130.49	0.00	0.00	0.00

Atom	x (Å)	y (Å)
Si1	0.000	1.061
Si2	0.000	-1.061
H3	1.174	1.974
H4	-1.174	-1.974

	Si1	Si2	H3	H4
Si1		2.1221	1.4867	3.2538
Si2	2.1221		3.2538	1.4867
H3	1.4867	3.2538		4.5925
H4	3.2538	1.4867	4.5925

	hartrees
Energy at 0K	-578.820798
Energy at 298.15K
HF Energy	-578.820798
Nuclear repulsion energy	62.315080

Number	Element	Mulliken
1	Si	-0.001
2	Si	-0.001
3	H	0.001
4	H	0.001

<r²>	57.115
(<r²>)^1/2	7.557

Number	Element	Mulliken
1	Si	0.111
2	Si	0.111
3	H	-0.111
4	H	-0.111

	x	y	z
x	5.956	-0.496	0.000
y	-0.496	15.892	0.000
z	0.000	0.000	7.526

All results from a given calculation for Si2H2 (disilyne)

using model chemistry: HF/SDD

States and conformations

Conformer 1 (D*H)

Conformer 2 (C2H)

Conformer 3 (C2V)

All results from a given calculation for Si₂H₂ (disilyne)