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	hartrees
Energy at 0K	-77.247180
Energy at 298.15K	-77.247188
HF Energy	-77.155556
Nuclear repulsion energy	24.670212

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	3562	3562	0.00	67.47	0.21	0.35
2	Σ_g	2049	2049	0.00	43.63	0.25	0.40
3	Σ_u	3469	3469	86.56	0.00	0.00	0.00
4	Π_g	530	530	0.00	1.04	0.75	0.86
4	Π_g	530	530	0.00	1.04	0.75	0.86
5	Π_u	768	768	80.24	0.00	0.00	0.00
5	Π_u	768	768	80.24	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.605
C2	0.000	0.000	-0.605
H3	0.000	0.000	1.668
H4	0.000	0.000	-1.668

	C1	C2	H3	H4
C1		1.2099	1.0633	2.2732
C2	1.2099		2.2732	1.0633
H3	1.0633	2.2732		3.3364
H4	2.2732	1.0633	3.3364

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP=FULL/6-31G**

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/6-31G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)