Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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You are here: Resources > Conversion Forms > B to I, I to B

Converting between rotational constants and moments of inertia

B = h/(8 π² c I)

Where B is the rotational constant (cm^-1)
h is Plancks constant (gm cm²/sec)
c is the speed of light (cm/sec)
I is the moment of inertia (gm cm²)

Enter a rotational constant or a moment of inertia in the appropriate box below and press the adjacent calculate button. The related quantities will appear in the other boxes.