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	hartrees
Energy at 0K	-77.233507
Energy at 298.15K	-77.233573
HF Energy	-77.233507
Nuclear repulsion energy	24.626286

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	3404	0.00	54.03	0.27	0.42
2	Σ_g	2078	1998	0.00	116.10	0.07	0.13
3	Σ_u	3433	3301	97.06	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	741	712	101.51	0.00	0.00	0.00
5	Π_u	741	712	101.51	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		1.2089	1.0717	2.2806
C2	1.2089		2.2806	1.0717
H3	1.0717	2.2806		3.3523
H4	2.2806	1.0717	3.3523

Number	Element	Mulliken
1	C	0.310
2	C	0.310
3	H	-0.310
4	H	-0.310

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBE1PBE/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>	17.174
(<r²>)^1/2	4.144

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBE1PBE/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)