ConstantID

Rydberg constant times c in Hz

Atomic & nuclearMeasured

R∞c = 3.289 841 960 2500(36) × 1015 Hz

Value
3.289 841 960 2500 × 1015 Hz
Standard uncertainty
3600 Hz
Relative uncertainty
1.1 × 10−12 (1.1 parts per trillion)
Status
Measured
Symbol
R∞c
Source
CODATA 2022 via NIST · NIST entry

Use in a calculation

# Rydberg constant times c in Hz, CODATA 2022 (NIST)
rydberg_constant_times_c_in_hz = 3.28984196025e15  # Hz, standard uncertainty 3600

# SciPy: scipy.constants.physical_constants['Rydberg constant times c in Hz']

What it is

The Rydberg constant expressed as a frequency, R∞c, about 3.29 × 10¹⁵ Hz.

In other units

UnitValue
GHz gigahertz3 289 841.960 25
THz terahertz3289.841 960 25

Converted with ConstantID's unit table; digits are rounded to the precision of the value, and a long exact value is rounded only for display. The relative uncertainty is unchanged by conversion to an exactly defined 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).

Rydberg constant times c in Hz: CODATA values 1998–2022 relative to the 2022 value, in parts per trillion, with one-standard-uncertainty bars−60−40−200+20+40+60parts per trillion1998200220062010201420182022

Relative uncertainty

Rydberg constant times c in Hz: relative standard uncertainty in each CODATA adjustment, logarithmic scale10⁻¹³10⁻¹²10⁻¹¹1998200220062010201420182022
CODATAValue (uncertainty)Relative uncertaintyChange from previous
20223.289 841 960 2500(36) × 10151.1 × 10−12 −0.1 σ of 2018
20183.289 841 960 2508(64) × 10151.9 × 10−12 −5.5 σ of 2014
20143.289 841 960 355(19) × 10155.8 × 10−12 −0.5 σ of 2010
20103.289 841 960 364(17) × 10155.2 × 10−12 +0.1 σ of 2006
20063.289 841 960 361(22) × 10156.7 × 10−12 +0.0 σ of 2002
20023.289 841 960 360(22) × 10156.7 × 10−12 −0.3 σ of 1998
19983.289 841 960 368(25) × 10157.6 × 10−12

“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).

Related constants

Atomic & nuclear a0 Bohr radius 5.291 772 105 44(82) × 10−11 m Atomic & nuclear re Classical electron radius 2.817 940 3205(13) × 10−15 m Atomic & nuclear λC Compton wavelength 2.426 310 235 38(76) × 10−12 m Atomic & nuclear α Fine-structure constant 7.297 352 5643(11) × 10−3 Atomic & nuclear Eh Hartree energy 4.359 744 722 2060(48) × 10−18 J Atomic & nuclear Eh Hartree energy in eV 27.211 386 245 981(30) eV Atomic & nuclear α−1 1/α 137.035 999 177(21) Atomic & nuclear πℏ/me Quantum of circulation 3.636 947 5467(11) × 10−4 m2 s−1