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	hartrees
Energy at 0K	-76.828728
Energy at 298.15K	-76.829019
HF Energy	-76.828728
Nuclear repulsion energy	24.932456

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	3677	3348	0.00	39.88	0.35	0.52
2	Σ_g	2209	2011	0.00	138.03	0.06	0.12
3	Σ_u	3564	3246	100.58	0.00	0.00	0.00
4	Π_g	736	670	0.00	4.85	0.75	0.86
4	Π_g	736	670	0.00	4.85	0.75	0.86
5	Π_u	840	765	115.56	0.00	0.00	0.00
5	Π_u	840	765	115.56	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.596
C2	0.000	0.000	-0.596
H3	0.000	0.000	1.659
H4	0.000	0.000	-1.659

	C1	C2	H3	H4
C1		1.1921	1.0625	2.2547
C2	1.1921		2.2547	1.0625
H3	1.0625	2.2547		3.3172
H4	2.2547	1.0625	3.3172

Number	Element	Mulliken
1	C	0.252
2	C	0.252
3	H	-0.252
4	H	-0.252

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: HF/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>	17.002
(<r²>)^1/2	4.123

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: HF/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)