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	hartrees
Energy at 0K	-76.178234
Energy at 298.15K	-76.176963
HF Energy	-76.178234
Nuclear repulsion energy	20.236483

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ	3576	3235	52.49
2	Σ	1882	1703	1.24
3	Π	610	552	34.24
3	Π	610	552	34.24

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.475
C2	0.000	0.000	0.730
H3	0.000	0.000	-1.530

	C1	C2	H3
C1		1.2041	1.0550
C2	1.2041		2.2591
H3	1.0550	2.2591

Number	Element	Mulliken
1	C	-0.946
2	C	-0.338
3	H	1.284

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

using model chemistry: HF/daug-cc-pVTZ

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>	13.986
(<r²>)^1/2	3.740

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

using model chemistry: HF/daug-cc-pVTZ

States and conformations

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