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	hartrees
Energy at 0K	-77.299579
Energy at 298.15K	-77.299724
HF Energy	-77.187162
Nuclear repulsion energy	24.826771

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	3539	3383	0.00	57.98	0.27	0.43
2	Σ_g	2033	1943	0.00	63.53	0.16	0.28
3	Σ_u	3435	3284	91.03	0.00	0.00	0.00
4	Π_g	634	606	0.00	3.40	0.75	0.86
4	Π_g	634	606	0.00	3.40	0.75	0.86
5	Π_u	766	732	93.79	0.00	0.00	0.00
5	Π_u	766	732	93.79	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.600
C2	0.000	0.000	-0.600
H3	0.000	0.000	1.660
H4	0.000	0.000	-1.660

	C1	C2	H3	H4
C1		1.2010	1.0592	2.2602
C2	1.2010		2.2602	1.0592
H3	1.0592	2.2602		3.3194
H4	2.2602	1.0592	3.3194

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP=FULL/cc-pVTZ

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: B2PLYP=FULL/cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)