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	hartrees
Energy at 0K	-77.125243
Energy at 298.15K	-77.125039
HF Energy	-76.825201
Nuclear repulsion energy	24.536348

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3549	3549
2	Σ_g	2008	2008
3	Σ_u	3454	3454
4	Π_g	419	419
4	Π_g	418	418
5	Π_u	729	729
5	Π_u	728	728

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.674
H4	0.000	0.000	-1.674

	C1	C2	H3	H4
C1		1.2187	1.0649	2.2836
C2	1.2187		2.2836	1.0649
H3	1.0649	2.2836		3.3485
H4	2.2836	1.0649	3.3485

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CCSD(T)=FULL/6-31+G**

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(T)=FULL/6-31+G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)