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Chemistry - MolPrincipalMoments

Syntax:
= MolPrincipalMoments(AtomsXYZ)

Description:
Returns the principal moments of inertia of a molecule.

The corresponding axis of inertia are given by the function MolPrincipalAxis. The i-th moment corresponds to the i-th column vector returned by the MolPrincipalAxis function.

AtomsXYZ: The cells that contain in column 1 the atomic symbol and in columns 2 to 4 the XYZ coordinates.

MolPrincipalMoments is an array function. Select 3 cells (1 row, 3 columns) and enter the formula. Then press CTRL+SHIFT+ENTER to create the array formula.

Example:
Calculate the principal axis of CO2

     A     B     C     D
1   C     0     0     0
2   O     1    0     0
3   O     -1    0     0

Select cells B5:D5. Enter the following formula
=MolPrincipalMoments(A1:D3)
Press CTRL+SHIFT+ENTER

Result:
     A     B     C     D
1   C     0     0     0
2   O     1    0     0
3   O     -1    0     0
4        
5        31.9 31.9 0