ConstantID

Atomic unit of magnetizability

UnitsMeasured

e2a02/me = 7.891 036 5794(49) × 10−29 J T−2

Value
7.891 036 5794 × 10−29 J T−2
Standard uncertainty
4.9 × 10−38 J T−2
Relative uncertainty
6.2 × 10−10 (621 parts per trillion)
Status
Measured
Symbol
e2a02/me
Source
CODATA 2022 via NIST · NIST entry

Use in a calculation

# atomic unit of magnetizability, CODATA 2022 (NIST)
atomic_unit_of_magnetizability = 7.8910365794e-29  # J T^-2, standard uncertainty 4.9e-38

# SciPy: scipy.constants.physical_constants['atomic unit of magnetizability']

What it is

The unit of magnetizability in the Hartree system of atomic units, where the electron mass, the elementary charge, ħ and 4πε₀ are all set to 1. Its value here is the SI equivalent of one atomic unit.

How the value changed, 1998–2022

Each point is one CODATA adjustment, plotted as its difference from the 2022 value; the bars show one standard uncertainty (an arrowhead means the bar runs off the chart).

atomic unit of magnetizability: CODATA values 1998–2022 relative to the 2022 value, in parts per billion, with one-standard-uncertainty bars−40−200+20+40parts per billion1998200220062010201420182022

Relative uncertainty

atomic unit of magnetizability: relative standard uncertainty in each CODATA adjustment, logarithmic scale10⁻¹⁰10⁻⁹10⁻⁸10⁻⁷1998200220062010201420182022
CODATAValue (uncertainty)Relative uncertaintyChange from previous
20227.891 036 5794(49) × 10−296.2 × 10−10 −4.5 σ of 2018
20187.891 036 6008(48) × 10−296.1 × 10−10 +1.4 σ of 2014
20147.891 036 5886(90) × 10−291.1 × 10−9 −1.4 σ of 2010
20107.891 036 607(13) × 10−291.6 × 10−9 +6.4 σ of 2006
20067.891 036 433(27) × 10−293.4 × 10−9 −1.3 σ of 2002
20027.891 036 60(13) × 10−291.6 × 10−8 +1.4 σ of 1998
19987.891 036 41(14) × 10−291.8 × 10−8

“Change from previous” is the shift in the value divided by the standard uncertainty of the previous adjustment. Earlier values are converted into the current unit where NIST changed it (for example J s to J Hz⁻¹).