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 C₄H₆ (Cyclobutene)

Property		Experiment	Calculated	Comparison
Energies Entropies	Enthalpy 298.15K	x
	Enthalpy 0K	x
	Energy 0K		306
	Energy 298.15K		294
	Atomization Enthalpy 298.15K	x	208	x
	Atomization Enthalpy 0K	x	208	x
	Entropy (298.15K)	x	178	x
	Entropy at any temperature		178
	Integrated Heat Capacity	x	178	x
	Heat Capacity (Cp)	x	178	x
	Nuclear Repulsion Energy		255
	HOMO-LUMO Energies		256
	Barriers to Internal Rotation		0
Geometries	Cartesians	x	229
	Internal Coordinates	x	228	x
	Products of moments of inertia	x	248	x
	Rotational Constants	x	253	x
	Point Group		253
Vibrations	Vibrational Frequencies	fun.	245	x
	Vibrational Intensities		263
	Zero-point energies	x	245	x
	Vibrational scaling factors	x
	Anharmonic frequencies and constants		1
	Raman frequencies and intensities		5
Electronic States	Electronic states	x	0
Electrostatics	Atom charges		198
	Dipole	x	222	x
	Quadrupole	x	204	x
	Polarizability		185
Other results	Spin		0
	Number of basis functions		6
	Conformations		1