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This article explores electron properties through molecular orbital plots, covering key aspects such as plotting the electron density, shading based on sign changes, and understanding orbital normalization in closed-shell molecules. We delve into population analysis to decompose total electron density into contributions from individual atoms or basis functions. Additionally, the dipole moment for Hartree-Fock wavefunctions is discussed, highlighting its calculation through expectation values, density matrices, and dipole integrals over basis functions, along with concepts of electron density and electrostatic potential.
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Chemistry 6440 / 7440 One Electron Properties
Molecular Orbital Plots • plot a surface where |i(r)|2 = c • i(r) can have positive and negative values • shade in different colors • only the change in sign matters, not the absolute sign
Population Analysis • divide up the total electron density into contributions from the individual atoms or basis functions • each orbital is normalized • in a closed shell molecule, each occupied orbital contains 2 electrons (Ne is the total number of electrons)
Population Analysis • each orbital is a linear combination of basis functions • plug into the expression for the total number of electrons and rearrange terms
Dipole Moment • for Hartree-Fock wavefunctions, the dipole is the expectation value of the classical expression for the dipole • can be written in terms of the density matrix and a set of dipole integrals over the basis functions
Electron Density • energy of a unit test charge placed at rC Electrostatic Potential