Category: Notekeeping

1 2273  1 Comment on Plotting molecular electrostatic potential surfaces (MEPS) with ORCA
Posted in Notekeeping ORCA

Plotting molecular electrostatic potential surfaces (MEPS) with ORCA

The orca_vpot program calculates the electrostatic potential for a set of points provided by the user. But it can be boring or hard. here is how you can do it.

0 1211  0 Comment on Non-Interactive plotting using orca_plot
Posted in Notekeeping ORCA

Non-Interactive plotting using orca_plot

ORCA provides a convenient way to plot orbitals and densities in the form of a small binary called orca_plot. Here is how to use it more conveniently.

0 1354  0 Comment on How can Spin-Orbit-Coupling allow interactions between states with different multiplicities?
Posted in Notekeeping Quantum Mechanics

How can Spin-Orbit-Coupling allow interactions between states with different multiplicities?

Here’s a longer sketch of what Paul’s comment is describing. In the absence of spin–orbit…

0 933  0 Comment on Why is manganese(II) colored although the transition should be spin-forbidden?
Posted in Notekeeping Quantum Mechanics

Why is manganese(II) colored although the transition should be spin-forbidden?

Selection rules The intensity of the transition from a state to a state is governed…

0 1155  0 Comment on Dynamic versus static electronic correlation
Posted in Notekeeping Quantum Mechanics

Dynamic versus static electronic correlation

In quantum chemistry, when a nomenclature in which one distinguishes between “static” and “dynamic” correlation…

0 894  0 Comment on The spin 1/2
Posted in Notekeeping

The spin 1/2

Particles with spin 1/2, like the electron, must perform two 360° rotations to return to…