Atomic unit of electric quadrupole moment = 4.486 551 5185 × 10⁻⁴⁰ C·m²

Name: Atomic unit of electric quadrupole moment — CODATA 2022 value
Creator: NIST

Value: 4.486 551 5185 × 10⁻⁴⁰
Unit: C·m²
Uncertainty: 0.000 000 0014 × 10⁻⁴⁰
Copy-ready: 4.4865515185e-40

The atomic unit of electric quadrupole moment: the natural size of electric quadrupole moment in the Hartree system, where ℏ, e, mₑ and 4πε₀ all equal 1.

Quantum-chemistry and atomic-physics codes report electric quadrupole moment in atomic units; multiply a result by this value to get it in SI.

NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.

Atomic units

Atomic unit of 1st hyperpolarizability Atomic unit of 2nd hyperpolarizability Atomic unit of charge density Atomic unit of current Atomic unit of electric dipole moment Atomic unit of electric field Atomic unit of electric field gradient Atomic unit of electric polarizability Atomic unit of electric potential Atomic unit of electric quadrupole moment Atomic unit of force Atomic unit of magnetic dipole moment Atomic unit of magnetic flux density Atomic unit of magnetizability Atomic unit of momentum Atomic unit of permittivity Atomic unit of time Atomic unit of velocity

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Atomic units

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