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	hartrees
Energy at 0K	-76.277299
Energy at 298.15K	-76.275608
HF Energy	-76.103589
Nuclear repulsion energy	19.732773

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ	3490	3490
2	Σ	1946	1946
3	Π	352	352
3	Π	352	352

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.489
C2	0.000	0.000	0.749
H3	0.000	0.000	-1.558

	C1	C2	H3
C1		1.2383	1.0688
C2	1.2383		2.3071
H3	1.0688	2.3071

Number	Element	Mulliken
1	C	-0.251
2	C	-0.053
3	H	0.304

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>	14.268
(<r²>)^1/2	3.777

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)