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State	Conformation	minimum conformation	conformer description	state description
1	1	yes	C*V	²Σ
1	2	no	CS	²A^'

	hartrees
Energy at 0K	-76.531683
Energy at 298.15K
HF Energy	-76.531683
Nuclear repulsion energy	20.087198

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ	3381	3359	58.40
2	Σ	2031	2018	4.66
3	Π	295i	293i	17.12
3	Π	295i	293i	17.12

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.476
C2	0.000	0.000	0.734
H3	0.000	0.000	-1.548

	C1	C2	H3
C1		1.2108	1.0718
C2	1.2108		2.2826
H3	1.0718	2.2826

All results from a given calculation for C₂H (Ethynyl radical)

using model chemistry: PBEPBE/aug-cc-pVTZ

States and conformations

Conformer 1 (C*V)

Conformer 2 (CS)

	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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Number	Element	Mulliken
1	C	-0.403
2	C	-0.029
3	H	0.433

	x	y	z	Total
	0.000	0.000	-0.793	0.793
CHELPG
AIM
ESP

<r²>	14.114
(<r²>)^1/2	3.757

Number	Element	Mulliken
1	C	-0.403
2	C	-0.029
3	H	0.433

All results from a given calculation for C2H (Ethynyl radical)

using model chemistry: PBEPBE/aug-cc-pVTZ

States and conformations

Conformer 1 (C*V)

Conformer 2 (CS)

All results from a given calculation for C₂H (Ethynyl radical)