Physical Constants and Reference Tables

Section C.1 Physical Constants and Reference Tables

Fundamental constants of nature, with values from CODATA 2022.

Table C.1.1. Fundamental Physical Constants

Constant	Symbol	Value	Unit	Relative Uncertainty
Speed of light in vacuum	\(c\)	299792458	m⋅s⁻¹	exact
Planck constant	\(h\)	6.62607015 × 10⁻³⁴	J⋅s	exact
Reduced Planck constant	\(\hbar = h/2\pi\)	1.054571817 × 10⁻³⁴	J⋅s	exact
Elementary charge	\(e\)	1.602176634 × 10⁻¹⁹	C	exact
Boltzmann constant	\(k_B\)	1.380649 × 10⁻²³	J⋅K⁻¹	exact
Avogadro constant	\(N_A\)	6.02214076 × 10²³	mol⁻¹	exact

Constants commonly used in quantum mechanics and atomic physics.

Table C.1.2. Quantum Mechanical Constants

Constant	Symbol	Value	Unit
Bohr radius	\(a_0\)	5.29177210903 × 10⁻¹¹	m
Rydberg constant	\(R_\infty\)	10967758.34	m⁻¹
Fine-structure constant	\(\alpha\)	7.2973525693 × 10⁻³	dimensionless
Electron rest mass	\(m_e\)	9.1093837015 × 10⁻³¹	kg

Constants used in thermodynamics and statistical mechanics.

Table C.1.3. Thermodynamic Constants

Constant	Symbol	Value	Unit
Gas constant	\(R = N_A k_B\)	8.314462618	J⋅mol⁻¹⋅K⁻¹
Standard atmosphere	\(atm\)	101325	Pa
Standard temperature and pressure	\(STP\)	273.15 K, 100 kPa	—

Useful conversion factors between common units.

Table C.1.4. Energy Unit Conversions