This article summarizes technical advances contained in the fifth major release of the Q-
Chem quantum chemistry program package, covering developments since 2015. A …

Electronically excited states of molecules are at the heart of photochemistry, photophysics,
as well as photobiology and also play a role in material science. Their theoretical description …

Hund's multiplicity rule states that a higher spin state has a lower energy for a given
electronic configuration. Rephrasing this rule for molecular excited states predicts a positive …

Phosphorescence is a phenomenon of delayed luminescence that corresponds to the
radiative decay of the molecular triplet state. As a general property of molecules …

The photophysics and photochemistry of DNA is of great importance due to the potential
damage of the genetic code by UV light. Quantum mechanical studies have played a key …

The electronic properties of finite-sized graphene fragments are strongly dependent on their
topological structures. The existence of two or more extended zigzag edges could lead to …

This article presents a perspective on Kohn-Sham density functional theory (KS-DFT) for
electronic structure calculations in chemical physics. This theory is in widespread use for …

The classic density-functional theory (DFT) formalism introduced by Hohenberg, Kohn, and
Sham in the mid-1960s is based on the idea that the complicated N-electron wave function …

In the thirty-two years since the birth of the foundational theorems, time-dependent density
functional theory has had a tremendous impact on calculations of electronic spectra and …

Carbon dots (CDs), including graphene quantum dots, carbon nanodots, carbon quantum
dots, and carbonized polymer dots, belong to extensively studied nanomaterials with a very …