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 C₂H₂ (Acetylene)

Property		Experiment	Calculated	Comparison
Energies Entropies	Enthalpy 298.15K	x
	Enthalpy 0K	x
	Energy 0K		964
	Energy 298.15K		956
	Atomization Enthalpy 298.15K	x	126	x
	Atomization Enthalpy 0K	x	131	x
	Entropy (298.15K)	x	91	x
	Entropy at any temperature		91
	Integrated Heat Capacity	x	91	x
	Heat Capacity (Cp)	x	91	x
	Nuclear Repulsion Energy		931
	HOMO-LUMO Energies		910
	Barriers to Internal Rotation		0
Geometries	Cartesians	x	896
	Internal Coordinates	x	896	x
	Products of moments of inertia	x	907	x
	Rotational Constants	x	911	x
	Point Group		915
Vibrations	Vibrational Frequencies	fun.	911	x
	Vibrational Intensities		1047
	Zero-point energies	x	911	x
	Vibrational scaling factors	x
	Anharmonic frequencies and constants
	Raman frequencies and intensities		417
Electronic States	Electronic states	x	0
Electrostatics	Atom charges		499
	Dipole	x	530	x
	Quadrupole	x	509	x
	Polarizability	x	553	x
Other results	Spin		0
	Number of basis functions		167
	Conformations		1