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	hartrees
Energy at 0K	-77.254910
Energy at 298.15K	-77.254890
HF Energy	-77.164021
Nuclear repulsion energy	24.514735

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	3525	3525	0.00	62.32	0.25	0.40
2	Σ_g	2014	2014	0.00	111.20	0.06	0.11
3	Σ_u	3426	3426	96.23	0.00	0.00	0.00
4	Π_g	523	523	0.00	2.67	0.75	0.86
4	Π_g	523	523	0.00	2.67	0.75	0.86
5	Π_u	729	729	96.52	0.00	0.00	0.00
5	Π_u	729	729	96.52	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.679
H4	0.000	0.000	-1.679

	C1	C2	H3	H4
C1		1.2175	1.0701	2.2876
C2	1.2175		2.2876	1.0701
H3	1.0701	2.2876		3.3577
H4	2.2876	1.0701	3.3577

Number	Element	Mulliken
1	C	0.283
2	C	0.283
3	H	-0.283
4	H	-0.283

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP/daug-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>	17.368
(<r²>)^1/2	4.168

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B2PLYP/daug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)