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	hartrees
Energy at 0K	-77.132820
Energy at 298.15K	-77.132419
HF Energy	-76.847815
Nuclear repulsion energy	24.732294

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3545	3387	0.00
2	Σ_g	2044	1953	0.00
3	Σ_u	3450	3296	80.44
4	Π_g	316	302	0.00
4	Π_g	316	302	0.00
5	Π_u	741	708	100.65
5	Π_u	741	708	100.65

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.603
C2	0.000	0.000	-0.603
H3	0.000	0.000	1.666
H4	0.000	0.000	-1.666

	C1	C2	H3	H4
C1		1.2056	1.0632	2.2688
C2	1.2056		2.2688	1.0632
H3	1.0632	2.2688		3.3319
H4	2.2688	1.0632	3.3319

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD/TZVP

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/TZVP

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)