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Physical Measurement Laboratory

Triatomic Spectral Database, Special Units, Fundamental Constants, and Useful Conversion Factors

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5. Special Units, Fundamental Constants, and Useful Conversion Factors

 

5.a. Special Units

D  Abbreviation for Debye units (1 D = 10-18 electrostatic units of charge × centimeters, or 1 D = 3.335 64 × 10-30 coulomb meter).
cm-1       Reciprocal wavelength (wave number) employed as a unit proportional to energy.
Å Angstrom abbreviation for the unit of length in bond distances (1 Å = 10-10 m).

5.b. Fundamental Constants and Conversion Factors

  1973 Values used in present tables [23] 1998 Values [24]
A · Ia = 5.053 790 5(85) × 105 MHz · u · Å2, = 5.053 790 06(51) × 105 MHz · u · Å2
h = 6.626 176(36) × 10-34 J · s, = 6.626 068 76(52) × 10-34 J · s
c = 2.997 924 58(1) × 108 m · s-1, = 299 792 458 m · s-1
1 cm-1 ≅ 1.986 478(11) × 10-23 J,

≅ 11.962 66 J mol-1 ,

≅ 29 979.2458 MHz  ,		 ≅ 1.986 445 44(16) × 10-23 J

≅ 11.962 66 J mol-1 

≅ 29 979.2458 MHz  
1 u = 1.660 565 5(86) × 10-27 kg . = 1.660 538 73(13) × 10-27 kg .
Analytical chemistry, Atomic / molecular / quantum and Reference data

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Created May 10, 2018, Updated November 15, 2019