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	hartrees
Energy at 0K	-76.997975
Energy at 298.15K	-76.997626
HF Energy	-76.789164
Nuclear repulsion energy	24.294920

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3465	3465
2	Σ_g	1963	1963
3	Σ_u	3368	3368
4	Π_g	360	360
4	Π_g	360	360
5	Π_u	700	700
5	Π_u	700	700

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.616
C2	0.000	0.000	-0.616
H3	0.000	0.000	1.690
H4	0.000	0.000	-1.690

	C1	C2	H3	H4
C1		1.2310	1.0743	2.3053
C2	1.2310		2.3053	1.0743
H3	1.0743	2.3053		3.3796
H4	2.3053	1.0743	3.3796

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD(TQ)/6-31G

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(TQ)/6-31G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)