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	hartrees
Energy at 0K	-76.587188
Energy at 298.15K	-76.585710
HF Energy	-76.587188
Nuclear repulsion energy	20.225604

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ	3528	3368	56.87
2	Σ	2110	2014	5.04
3	Π	461	441	0.55
3	Π	461	441	0.55

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.473
C2	0.000	0.000	0.729
H3	0.000	0.000	-1.537

	C1	C2	H3
C1		1.2027	1.0637
C2	1.2027		2.2664
H3	1.0637	2.2664

Number	Element	Mulliken
1	C	0.022
2	C	-0.257
3	H	0.235

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

using model chemistry: mPW1PW91/6-31G(2df,p)

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>	13.619
(<r²>)^1/2	3.690

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

using model chemistry: mPW1PW91/6-31G(2df,p)

States and conformations

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