TransitionDipolePlot - Maple Help

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QuantumChemistry

 TransitionDipolePlot
 plot the transition dipole moment of a ground-to-excited-state transition

 Calling Sequence TransitionDipolePlot(molecule, method, state, 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' state - (optional)  state = integer where the integer specifies the excited state (default = 1) options - (optional) equation(s) of the form option = value where option is any valid option of the chosen method

Description

 • TransitionDipolePlot plots the electronic transition dipole moment of a ground-to-excited-state transition.
 • The index of the excited state can be set with the optional keyword state, i.e. state = 1 (default) sets the first excited state where the excited states are ordered from lowest to highest in energy.
 • Methods, set by the method keyword, include 'HartreeFock' (default) and 'DensityFunctional'.
 • The number n of excited states in the calculation is determined by the optional keyword nstates.  If nstates = n, then n singlet and n triplet states are computed.  If nstates=[n,m], then n singlet and m triplet states are computed.  By default, nstates = 6.
 • When the HartreeFock method is selected, transition dipole moments can be computed by either the time-dependent Hartree-Fock (TDHF) or the configuration interaction singles (CIS) method.  By default TDHF is performed.  TDHF and CIS can be directly selected by setting the optional keyword excited_states to the string "TDHF" or "CIS".
 • When the DensityFunctional method is selected, transition dipole moments can be computed by either the time-dependent density functional theory (TDDFT) or the Tamm-Dancoff approximation (TDA) method.  By default TDDFT is performed.  TDDFT and TDA can be directly selected by setting the optional keyword excited_states to the string "TDDFT" or "TDA".
 • The result depends upon the chosen molecule, method, and basis set among other options such as charge, spin, and symmetry.  The ground-state molecule must be in a singlet state, that is spin = 0.
 • The command only works with methods that return excitation energies.
 • Because the methods employ Maple remember tables, the procedure only computes the transition dipole moment if it has not been previously computed by calling the method directly or indirectly through another property.

Examples

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

Let us plot the transition dipole moments of the $\mathrm{uracil}$ molecule computed with the Hartree-Fock (TDHF) method

First, we define the molecule's geometry with the MolecularGeometry command

 >
 ${\mathrm{molecule}}{≔}\left[\left[{"O"}{,}{2.32640000}{,}{0.96510000}{,}{0.00010000}\right]{,}\left[{"O"}{,}{-2.29720000}{,}{1.02320000}{,}{0.00050000}\right]{,}\left[{"N"}{,}{0.01800000}{,}{1.01990000}{,}{-0.00020000}\right]{,}\left[{"N"}{,}{1.16370000}{,}{-1.02210000}{,}{0.00010000}\right]{,}\left[{"C"}{,}{1.25240000}{,}{0.36290000}{,}{0}\right]{,}\left[{"C"}{,}{-1.23150000}{,}{0.41410000}{,}{-0.00040000}\right]{,}\left[{"C"}{,}{-0.02680000}{,}{-1.69550000}{,}{0.00020000}\right]{,}\left[{"C"}{,}{-1.20490000}{,}{-1.06760000}{,}{-0.00020000}\right]{,}\left[{"H"}{,}{0.03820000}{,}{2.03570000}{,}{-0.00010000}\right]{,}\left[{"H"}{,}{2.01870000}{,}{-1.57020000}{,}{0.00040000}\right]{,}\left[{"H"}{,}{-2.14430000}{,}{-1.60630000}{,}{-0.00020000}\right]{,}\left[{"H"}{,}{0.04690000}{,}{-2.77610000}{,}{0.00040000}\right]\right]$ (1)

Second, we plot uracil with the PlotMolecule command

 > $\mathrm{PlotMolecule}\left(\mathrm{molecule}\right);$

Finally, we plot the transition dipole moment of the ground and first-excited state

 > $\mathrm{TransitionDipolePlot}\left(\mathrm{molecule},\mathrm{state}=1\right);$

By left clicking on the plot, styles can be customized, and the plot can be exported to a range of image files including PNG and EPS.

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