Imaginary-time path-integral or 'ring-polymer'methods have been used to simulate quantum
(Boltzmann) statistical properties since the 1980s. This article reviews the more recent …

Instanton theory provides a simple description of a quantum tunnelling process in terms of
an optimal tunnelling pathway. The theory is rigorously based on quantum mechanics …

Progress in the atomic-scale modeling of matter over the past decade has been tremendous.
This progress has been brought about by improvements in methods for evaluating …

Reaction rate theory has been at the center of physical chemistry for well over one hundred
years. The evolution of the theory is not only of historical interest. Reliable and accurate …

In this Perspective we show that semiclassical methods provide a rigorous hierarchical way
to study the vibrational spectroscopy and kinetics of complex molecular systems. The time …

Since the earliest explorations of quantum mechanics, it has been a topic of great interest
that quantum tunneling allows particles to penetrate classically insurmountable barriers …

Multi-electron, multi-proton transfer is important in a wide spectrum of processes spanning
biological, chemical and physical systems. These reactions have attracted significant …

Investigating how formamide forms in the interstellar medium is a hot topic in astrochemistry,
which can contribute to our understanding of the origin of life on Earth. We have constructed …

We introduce an approach for calculating perturbative corrections to the ring-polymer
instanton approximation to tunneling splittings (RPI+ PC) by computing higher-order terms in …

The interstellar medium (ISM) is rich in molecules, from simple diatomic to complex organic
ones, some of which have a biotic potential. A notable example, in this respect, is …