Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All data (experiment and calculated) in the CCCBDB for C₂H (Ethynyl radical)

Property		Experiment	Calculated	Comparison
Energies Entropies	Enthalpy 298.15K	x
	Enthalpy 0K	x
	Energy 0K		687
	Energy 298.15K		502
	Atomization Enthalpy 298.15K	x	51	x
	Atomization Enthalpy 0K	x	54	x
	Entropy (298.15K)	x	21	x
	Entropy at any temperature		21
	Integrated Heat Capacity	x	21	x
	Heat Capacity (Cp)	x	21	x
	Nuclear Repulsion Energy		559
	HOMO-LUMO Energies		469
	Barriers to Internal Rotation		666
Geometries	Cartesians	x	599
	Internal Coordinates	x	599	x
	Products of moments of inertia	x	526	x
	Rotational Constants	x	536	x
	Point Group		564
Vibrations	Vibrational Frequencies	fun.	524	x
	Vibrational Intensities		639
	Zero-point energies	x	524	x
	Vibrational scaling factors	x
	Anharmonic frequencies and constants
	Raman frequencies and intensities		10
Electronic States	Electronic states	x	0
Electrostatics	Atom charges		318
	Dipole		384
	Quadrupole		301
	Polarizability		399
Other results	Spin		570
	Number of basis functions		97
	Conformations		2	x