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Calculate Populations and Valences tool

Use the Calculate Populations and Valences tool to calculate populations and valences of atomic orbitals, atomic shells, atoms, molecular fragments.
For the population analisys Simple and Mulliken schemes are available.

Performing population analysis

Calculating quantum-chemical valence indexes

To show the Calculate Populations and Valences tool window click the menu Tools ---> Calculate Populations and Valences
  • To the right of the appeared window select one of the calculations of your document;
  • From the list below select "Calculate populations" or "Calculate valences".
  • If this is an open-shell calculation then in the Spin section choose the populations types to be calculated: Alpha, Beta, Total(=Alpha+Beta), Spin(Alpha-Beta);
  • In the Contributions types section select calculation scheme: Simple or Mulliken (notice that for Mulliken-scheme overlap integrals must be calculated, so the coefficients matrix must be nonsingular);
  • In the print populations section choose print parameters (Atomic orbitals, AO shells, Atoms, molacular fragments).
You can choose/change all the options and Chemissian will update "on fly" the left window space where the calculation result is presented.
Press the Save button in the lower right corner of the window to save the calculation result into a text file.