MOOccupationsPlot - Maple Help

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QuantumChemistry

 MOOccupationsPlot
 display 2D plot of the molecular-orbital (MO) occupations

 Calling Sequence MOOccupationsPlot(molecule, method, options)

Parameters

 molecule - list of lists; each list has 4 elements, the string of an atom's symbol and atom's x, y, and z coordinates method - (optional)  method = name/procedure where name is one of 'HartreeFock' (default), 'DensityFunctional', options - (optional) equation(s) of the form option = value where option is any valid option of the chosen method

Description

 • MOOccupationsPlot displays the occupations of the molecular orbitals (MOs).
 • Each occupation is represented by a horizontal line.  The most-filled N/2 occupations are colored blue with the rest colored red.
 • The MO occupations are the eigenvalues of the one-electron reduced density matrix (1-RDM), known as the natural occupations.
 • The default method is 'HartreeFock' method whose correlation energy is 0.
 • The result depends upon the chosen molecule, method, and basis set among other options such as charge, spin, and symmetry.

Examples

 > $\mathrm{with}\left(\mathrm{QuantumChemistry}\right):$

Consider the molecule hydrogen peroxide

 >
 ${\mathrm{mol}}{≔}\left[\left[{"O"}{,}{0.72470000}{,}{0}{,}{0}\right]{,}\left[{"O"}{,}{-0.72470000}{,}{0}{,}{0}\right]{,}\left[{"H"}{,}{0.82330000}{,}{-0.70000000}{,}{-0.66760000}\right]{,}\left[{"H"}{,}{-0.82330000}{,}{-0.61750000}{,}{0.74460000}\right]\right]$ (1)

The MO occupations from the Hartree-Fock method are either 1 (oocupied) or 0 (unoccupied)

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In contrast, the MO occupations from the parametric 2-RDM method are fractional

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