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	hartrees
Energy at 0K	-76.401192
Energy at 298.15K	-76.399532
HF Energy	-76.159327
Nuclear repulsion energy	20.067837

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ	3511	3511
2	Σ	2008	2008
3	Π	364	364
3	Π	364	364

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.479
C2	0.000	0.000	0.736
H3	0.000	0.000	-1.541

	C1	C2	H3
C1		1.2144	1.0627
C2	1.2144		2.2771
H3	1.0627	2.2771

Number	Element	Mulliken
1	C	-0.201
2	C	-0.001
3	H	0.202

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

using model chemistry: ROMP2/TZVP

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>	14.154
(<r²>)^1/2	3.762

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

using model chemistry: ROMP2/TZVP

States and conformations

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