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	hartrees
Energy at 0K	-75.706021
Energy at 298.15K	-75.704554
HF Energy	-75.706021
Nuclear repulsion energy	20.041093

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ	3399	3338	65.05
2	Σ	2075	2038	7.39
3	Π	469	461	4.07
3	Π	469	461	4.07

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.477
C2	0.000	0.000	0.736
H3	0.000	0.000	-1.552

	C1	C2	H3
C1		1.2136	1.0743
C2	1.2136		2.2879
H3	1.0743	2.2879

Number	Element	Mulliken
1	C	-0.220
2	C	-0.053
3	H	0.273

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

using model chemistry: LSDA/3-21G*

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>	13.921
(<r²>)^1/2	3.731

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

using model chemistry: LSDA/3-21G*

States and conformations

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