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	hartrees
Energy at 0K	-77.333227
Energy at 298.15K	-77.333369
HF Energy	-77.333227
Nuclear repulsion energy	24.607066

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	3528	3422	0.00	65.14	0.24	0.38
2	Σ_g	2074	2012	0.00	57.35	0.24	0.39
3	Σ_u	3426	3323	95.32	0.00	0.00	0.00
4	Π_g	629	610	0.00	1.23	0.75	0.86
4	Π_g	629	610	0.00	1.23	0.75	0.86
5	Π_u	774	751	76.66	0.00	0.00	0.00
5	Π_u	774	751	76.66	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	1.677
H4	0.000	0.000	-1.677

	C1	C2	H3	H4
C1		1.2099	1.0724	2.2823
C2	1.2099		2.2823	1.0724
H3	1.0724	2.2823		3.3547
H4	2.2823	1.0724	3.3547

Number	Element	Mulliken
1	C	0.001
2	C	0.001
3	H	-0.001
4	H	-0.001

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3LYPultrafine/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>	16.997
(<r²>)^1/2	4.123

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3LYPultrafine/cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)