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 He₂⁺ (helium diatomic cation)

Property		Experiment	Calculated	Comparison
Energies Entropies	Enthalpy 298.15K
	Enthalpy 0K
	Energy 0K		611
	Energy 298.15K		9
	Atomization Enthalpy 298.15K		0
	Atomization Enthalpy 0K		0
	Entropy (298.15K)		0
	Entropy at any temperature		0
	Integrated Heat Capacity		0
	Heat Capacity (Cp)		0
	Nuclear Repulsion Energy		591
	HOMO-LUMO Energies		526
	Barriers to Internal Rotation		0
Geometries	Cartesians	x	590
	Internal Coordinates	x	590	x
	Products of moments of inertia	x	599	x
	Rotational Constants	x	606	x
	Point Group		607
Vibrations	Vibrational Frequencies	fun. har.	606	x
	Vibrational Intensities		813
	Zero-point energies	x	606	x
	Vibrational scaling factors	x
	Anharmonic frequencies and constants
	Raman frequencies and intensities		5
Electronic States	Electronic states	x	0
Electrostatics	Atom charges		366
	Dipole		435
	Quadrupole		358
	Polarizability		384
Other results	Spin		606
	Number of basis functions		29
	Conformations		1