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	hartrees
Energy at 0K	-77.240419
Energy at 298.15K	-77.240486
HF Energy	-77.240419
Nuclear repulsion energy	24.630912

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	3540	3406	0.00	54.35	0.27	0.42
2	Σ_g	2077	1998	0.00	117.15	0.07	0.13
3	Σ_u	3433	3303	95.60	0.00	0.00	0.00
4	Π_g	582	560	0.00	3.24	0.75	0.86
4	Π_g	582	560	0.00	3.24	0.75	0.86
5	Π_u	740	712	101.12	0.00	0.00	0.00
5	Π_u	740	712	101.12	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.604
C2	0.000	0.000	-0.604
H3	0.000	0.000	1.676
H4	0.000	0.000	-1.676

	C1	C2	H3	H4
C1		1.2087	1.0715	2.2801
C2	1.2087		2.2801	1.0715
H3	1.0715	2.2801		3.3516
H4	2.2801	1.0715	3.3516

Number	Element	Mulliken
1	C	0.322
2	C	0.322
3	H	-0.322
4	H	-0.322

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HSEh1PBE/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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<r²>	17.171
(<r²>)^1/2	4.144

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HSEh1PBE/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)