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	hartrees
Energy at 0K	-77.192516
Energy at 298.15K	-77.192661
HF Energy	-76.854595
Nuclear repulsion energy	24.808448

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3523	3523	0.00
2	Σ_g	2045	2045	0.00
3	Σ_u	3428	3428	84.55
4	Π_g	635	635	0.00
4	Π_g	635	635	0.00
5	Π_u	767	767	91.74
5	Π_u	767	767	91.74

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.600
C2	0.000	0.000	-0.600
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.2009	1.0619	2.2628
C2	1.2009		2.2628	1.0619
H3	1.0619	2.2628		3.3247
H4	2.2628	1.0619	3.3247

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD/cc-pVQZ

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: QCISD/cc-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)