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	hartrees
Energy at 0K	-77.086839
Energy at 298.15K	-77.086808
HF Energy	-76.827359
Nuclear repulsion energy	24.520871

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3555	3555	0.00
2	Σ_g	2074	2074	0.00
3	Σ_u	3454	3454	87.09
4	Π_g	507	507	0.00
4	Π_g	507	507	0.00
5	Π_u	746	746	97.57
5	Π_u	746	746	97.57

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.608
C2	0.000	0.000	-0.608
H3	0.000	0.000	1.681
H4	0.000	0.000	-1.681

	C1	C2	H3	H4
C1		1.2157	1.0730	2.2886
C2	1.2157		2.2886	1.0730
H3	1.0730	2.2886		3.3616
H4	2.2886	1.0730	3.3616

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: CISD/aug-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: CISD/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)