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	hartrees
Energy at 0K	-76.600227
Energy at 298.15K	-76.600120
HF Energy	-76.393056
Nuclear repulsion energy	24.477379

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3467	3467
2	Σ_g	1990	1990
3	Σ_u	3366	3366
4	Π_g	480	480
4	Π_g	480	480
5	Π_u	716	716
5	Π_u	716	716

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.610
C2	0.000	0.000	-0.610
H3	0.000	0.000	1.680
H4	0.000	0.000	-1.680

	C1	C2	H3	H4
C1		1.2207	1.0693	2.2900
C2	1.2207		2.2900	1.0693
H3	1.0693	2.2900		3.3594
H4	2.2900	1.0693	3.3594

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD(TQ)/3-21G

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)/3-21G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)