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	hartrees
Energy at 0K	-76.379155
Energy at 298.15K
HF Energy	-76.139855
Nuclear repulsion energy	19.748015

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ	3471	3471
2	Σ	1961	1961
3	Π	266i	266i
3	Π	266i	266i

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.487
C2	0.000	0.000	0.748
H3	0.000	0.000	-1.564

	C1	C2	H3
C1		1.2352	1.0762
C2	1.2352		2.3114
H3	1.0762	2.3114

Number	Element	Mulliken
1	C	0.558
2	C	-0.489
3	H	-0.069

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

using model chemistry: ROMP2/aug-cc-pVDZ

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>	14.433
(<r²>)^1/2	3.799

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

using model chemistry: ROMP2/aug-cc-pVDZ

States and conformations

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