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	hartrees
Energy at 0K	-77.323201
Energy at 298.15K	-77.323376
HF Energy	-77.323201
Nuclear repulsion energy	24.853026

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	3514	3364	0.00	51.45	0.27	0.43
2	Σ_g	2068	1980	0.00	107.23	0.07	0.13
3	Σ_u	3412	3266	90.01	0.00	0.00	0.00
4	Π_g	663	635	0.00	3.55	0.75	0.86
4	Π_g	663	635	0.00	3.55	0.75	0.86
5	Π_u	767	735	100.30	0.00	0.00	0.00
5	Π_u	767	735	100.30	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.598
C2	0.000	0.000	-0.598
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.1969	1.0639	2.2608
C2	1.1969		2.2608	1.0639
H3	1.0639	2.2608		3.3247
H4	2.2608	1.0639	3.3247

Number	Element	Mulliken
1	C	-0.216
2	C	-0.216
3	H	0.216
4	H	0.216

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3PW91/6-311+G(3df,2p)

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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Calc. vs exp. Bad Vib. HF vs MP2 Bad scale factors Low excited states Oddities NaCN Is not linear FAQ Help Units Choose Units Energy Bond length Rotational Constant Moment of Inertia Dipole and Quadrupole Polarizability Explanations Hartree cm-1 Debye Credits Just show me Show me a calculated geometry Summary Using older interface Limit Basis sets Method options List Recent molecules Choose a few Molecules Number of atoms By heavy atoms Diatomics InChI Deuterated Dimers Geometry Point group Point group count Bonds types Isodesmic reactions Bad point group Multiple conformers, states Vibrations Big anharmonicity Energy Enthalpy at 0 Kelvin Similar molecules Similar Isomers Cis/trans Tautomers Multiple conformers, states Ions, Dipoles, etc. List Ions Ionization changes point group Dipole Quadrupole Polarizability Proton Affinities Index of CCCBDB Feedback Error form Wants
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<r²>	16.948
(<r²>)^1/2	4.117

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3PW91/6-311+G(3df,2p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)