Atomic units: Difference between revisions

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imported>John R. Brews
(add charge to table)
imported>John R. Brews
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|2.418 884 326 505(16) × 10<sup>−17</sup> s
|2.418 884 326 505(16) × 10<sup>−17</sup> s
|-
|-
|[[Reduced Planck constant]]
|Reduced [[Planck constant]]
|'''ℏ'''
|'''ℏ'''
|[[action]]
|[[action]]
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|[[energy]]
|[[energy]]
|4.359 744 17(75)  × 10<sup>−18</sup> J
|4.359 744 17(75)  × 10<sup>−18</sup> J
|-
|-
|[[a.u. velocity]]
|'''v<sub>B</sub>≡αc'''
|[[velocity]]
|2.187 691 2633(73) × 10<sup>6</sup> m/s
|-
|-
|}
|}
Here, ''c'' = [[speed of light]] and ''&alpha;'' = [[fine structure constant]].


==Notes==
==Notes==
<references/>
<references/>

Revision as of 13:06, 10 March 2011

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The atomic units, abbreviated a.u. is a set of units used in atomic calculations.[1][2]

Base units

Atomic base units [2]
Name Symbol Quantity Value in SI units
elementary charge e charge 1.602 176 53(14) × 10−19 C
Bohr radius (bohr) a0 length 0.529 177 2108(18) × 10−10 m
electron mass me mass 9.109 3826(16) × 10−31 kg
Reduced period of first Bohr orbit ℏ/Eh time 2.418 884 326 505(16) × 10−17 s
Reduced Planck constant action 1.054 571 68(18) × 10−34 Js
Hartree energy (hartree) Eh energy 4.359 744 17(75) × 10−18 J
a.u. velocity vB≡αc velocity 2.187 691 2633(73) × 106 m/s

Here, c = speed of light and α = fine structure constant.

Notes

  1. For an introduction, see Gordon W. F. Drake (2006). “§1.2 Atomic units”, Springer handbook of atomic, molecular, and optical physics, Volume 1, 2nd ed. Springer, p. 6. ISBN 038720802X. 
  2. 2.0 2.1 Tabulated values from Barry N. Taylor (2008). International System of Units (SI), Revised 2008 ed. DIANE Publishing, Table 7, p.33. ISBN 1437915582.