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	hartrees
Energy at 0K	-77.103598
Energy at 298.15K	-77.103676
HF Energy	-76.823797
Nuclear repulsion energy	24.404760

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3525	3525	0.00
2	Σ_g	2032	2032	0.00
3	Σ_u	3430	3430	85.57
4	Π_g	583	583	0.00
4	Π_g	583	583	0.00
5	Π_u	758	758	76.94
5	Π_u	758	758	76.94

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.611
C2	0.000	0.000	-0.611
H3	0.000	0.000	1.688
H4	0.000	0.000	-1.688

	C1	C2	H3	H4
C1		1.2220	1.0770	2.2990
C2	1.2220		2.2990	1.0770
H3	1.0770	2.2990		3.3760
H4	2.2990	1.0770	3.3760

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD=FULL/cc-pVDZ

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: CCSD=FULL/cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)