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 CH₃CH(CH₃)CH₃ (Isobutane)

Property		Experiment	Calculated	Comparison
Energies Entropies	Enthalpy 298.15K	x
	Enthalpy 0K	x
	Energy 0K		294
	Energy 298.15K		264
	Atomization Enthalpy 298.15K	x	34	x
	Atomization Enthalpy 0K	x	35	x
	Entropy (298.15K)	x	20	x
	Entropy at any temperature		20
	Integrated Heat Capacity	x	20	x
	Heat Capacity (Cp)	x	20	x
	Nuclear Repulsion Energy		275
	HOMO-LUMO Energies		260
	Barriers to Internal Rotation		0
Geometries	Cartesians	x	246
	Internal Coordinates	x	245	x
	Products of moments of inertia	x	250	x
	Rotational Constants	x	260	x
	Point Group		279
Vibrations	Vibrational Frequencies	fun.	253	x
	Vibrational Intensities		417
	Zero-point energies		253
	Vibrational scaling factors
	Anharmonic frequencies and constants		1
	Raman frequencies and intensities		5
Electronic States	Electronic states	x	0
Electrostatics	Atom charges		189
	Dipole	x	215	x
	Quadrupole		198
	Polarizability	x	220	x
Other results	Spin		0
	Number of basis functions		26
	Conformations		1