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	hartrees
Energy at 0K	-76.182439
Energy at 298.15K	-76.181173
HF Energy	-76.182439
Nuclear repulsion energy	20.250694

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ	3571	3571	51.99
2	Σ	1884	1884	1.30
3	Π	612	612	34.32
3	Π	612	612	34.32

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.474
C2	0.000	0.000	0.729
H3	0.000	0.000	-1.529

	C1	C2	H3
C1		1.2030	1.0552
C2	1.2030		2.2582
H3	1.0552	2.2582

Number	Element	Mulliken
1	C	-0.141
2	C	-0.020
3	H	0.161

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

using model chemistry: ROHF/cc-pVQZ

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>	13.956
(<r²>)^1/2	3.736

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

using model chemistry: ROHF/cc-pVQZ

States and conformations

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