The developments of the open-source OpenMolcas chemistry software environment since
spring 2020 are described, with a focus on novel functionalities accessible in the stable …

We present a general approach to converge excited state solutions to any quantum
chemistry orbital optimization process, without the risk of variational collapse. The resulting …

Photochemical reactions are widely modeled using the popular trajectory surface hop**
(TSH) method, an affordable mixed quantum-classical approximation to the full quantum …

We present a discussion of recent progress in excited‐state‐specific quantum chemistry and
quantum Monte Carlo alongside a demonstration of how a combination of methods from …

Hierarchy configuration interaction (hCI) has recently been introduced as an alternative
configuration interaction (CI) route combining excitation degree and seniority number and …

State-specific approximations can provide a more accurate representation of challenging
electronic excitations by enabling relaxation of the electron density. While state-specific …

State-specific electronic structure theory provides a route toward balanced excited-state
wave functions by exploiting higher-energy stationary points of the electronic energy …

We reexamine ΔCCSD, a state-specific coupled-cluster (CC) with single and double
excitations (CCSD) approach that targets excited states through the utilization of non-Aufbau …

In single-reference coupled-cluster (CC) methods, one has to solve a set of non-linear
polynomial equations in order to determine the so-called amplitudes that are then used to …

Symmetry provides a powerful machinery to classify, interpret, and understand quantum-
mechanical theories and results. However, most contemporary quantum chemistry packages …