# Atomic Constants

### - table or chart of atomic constants including symbol, value and units for values such as Rydberg constant, Bohr radius, Hartree energy, etc.

### In this section

Physical & fundamental constants pages include:

• Fundamental physical constants

• Universal constants

• Electromagnetic constants

• Atomic constants

• Electron constants

• Proton constants

• Neutron constants

• Physico-chemical constants

Atomic constants are used in many areas of science and electronics for a variety of calculations.

The atomic constants that come under the universal constants heading include items such as the Rydberg constant, Bohr radius, Hartree energy, etc.

Details for these atomic constants and more are given below. The constant name, symbol, value, units and the relative uncertainty are provided.

Constant name | Symbol of constant | Value | Units | Relative Uncertainty |
---|---|---|---|---|

Rydberg constant | R |
10.973 731 534 | m^-1 |
0.0012 |

Rydberg constant in hertz | |
3.289 841 9499 | 10^15 Hz |
0.0012 |

Rydberg constant in Joules | |
2.179 8741 | 10^-18 J |
0.60 |

Rydberg constant in eV | |
13.605 6981 | eV |
0.30 |

Bohr radius | a0 |
0.529 177 249 | 10^-10 m |
0.045 |

Hartree energy | Eh |
4.359 748 2 | 10^-18 J |
0.60 |

Hartree energy in eV | |
27.211 396 1 | eV |
0.30 |

Fine structure constant | α |
7.297 353 08 | 10^-3 |
0.045 |

Inverse fine structure constant | α^-1 |
137.035 989 5 | |
0.045 |

## Read more popular reference pages & tables . . . . . |
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• dBm / Watts table | • Trig functions | • Fourier series | • Constants |

• SI base units | • SI prefixes | • Sidereal time | • Greek letters |

• Resistivity | • Physical constants | • Capacitance | • Circuit symbols |

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