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	hartrees
Energy at 0K	-76.808839
Energy at 298.15K	-76.809100
HF Energy	-76.808839
Nuclear repulsion energy	24.760373

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	3432	0.00	55.71	0.18	0.31
2	Σ_g	2101	2023	0.00	42.46	0.29	0.46
3	Σ_u	3449	3322	89.06	0.00	0.00	0.00
4	Π_g	738	711	0.00	2.78	0.75	0.86
4	Π_g	738	711	0.00	2.78	0.75	0.86
5	Π_u	800	770	111.54	0.00	0.00	0.00
5	Π_u	800	770	111.54	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.602
C2	0.000	0.000	-0.602
H3	0.000	0.000	1.665
H4	0.000	0.000	-1.665

	C1	C2	H3	H4
C1		1.2037	1.0630	2.2667
C2	1.2037		2.2667	1.0630
H3	1.0630	2.2667		3.3298
H4	2.2667	1.0630	3.3298

Number	Element	Mulliken
1	C	-0.281
2	C	-0.281
3	H	0.281
4	H	0.281

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HSEh1PBE/3-21G

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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<r²>	16.851
(<r²>)^1/2	4.105

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HSEh1PBE/3-21G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)