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	hartrees
Energy at 0K	-76.368593
Energy at 298.15K	-76.366692
HF Energy	-76.133174
Nuclear repulsion energy	19.957586

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ	3543	3543
2	Σ	2011	2011
3	Π	264	264
3	Π	263	263

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.483
C2	0.000	0.000	0.740
H3	0.000	0.000	-1.545

	C1	C2	H3
C1		1.2226	1.0628
C2	1.2226		2.2854
H3	1.0628	2.2854

Number	Element	Mulliken
1	C	-0.150
2	C	-0.081
3	H	0.231

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

using model chemistry: ROMP2/6-31G**

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>	13.970
(<r²>)^1/2	3.738

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

using model chemistry: ROMP2/6-31G**

States and conformations

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