University Lecturer

Alex Thom is a University Professor in Theoretical Chemistry in the University of Cambridge. His research interests are in Theoretical and Computational Chemistry, specializing in method and software development.

Current projects involve the calculation of accurate electronic energies using Monte Carlo techniques, the description of excited states of medium-large molecules (from chromophores to single-molecule magnets) using new methodologies, and the application of Quantum Chemical Algorithms on Quantum Computers.

I am also a developer of the HANDE QMC package (version 1.6 released June 2022) which (amongst many features) performs Full Configuration Interaction Quantum Monte Carlo and Coupled Cluster Monte Carlo on molecular and solid-state systems, and am happy to be contacted with questions about using this or potential applications.

As part of the EXTRA Consortium, we have been looking at the development processes involved in writing scientific software on modern reconfigurable architectures (principally FPGAs), and currently have projects implementing Quantum Monte Carlo methods on these architectures. I am also part of the Cambridge Leverhulme Centre for Life in the Universe.

PhD and MPhil Positions

If you are interested in pursuing an MPhil or PhD in my group, please contact my secretary, sending a CV by email.  Applications to begin October 2025 are now open. For consideration in the funding competition applications must be received by 2nd December 2025.  Applicants with external funding will still be able to apply in early 2026. 

 

I am part of the Centre for Scientific Computing as well as the Leverhulme Centre for Life in the Universe which offer some funded PhD positions, and I am happy to accept applicants for the MPhil in Scientific Computing and also Chemistry. Some example project ideas can be found here.

Dr Thom discusses his research

Publications

Complex adiabatic connection: A hidden non-Hermitian path from ground to excited states
HGA Burton, AJW Thom, P-F Loos
Journal of Chemical Physics
(2019)
150
Exciting determinants in Quantum Monte Carlo: Loading the dice with fast, low memory weights
VA Neufeld, AJW Thom
Journal of Chemical Theory and Computation
(2019)
15
The HANDE-QMC project: open-source stochastic quantum chemistry from the ground state up
JS Spencer, NS Blunt, S Choi, J Etrych, M-A Filip, WMC Foulkes, RST Franklin, WJ Handley, FD Malone, VA Neufeld, R Di Remigio, TW Rogers, CJC Scott, JJ Shepherd, WA Vigor, J Weston, R Xu, AJW Thom
(2018)
Large Scale Parallelization in Stochastic Coupled Cluster
JS Spencer, VA Neufeld, WA Vigor, RST Franklin, AJW Thom
The Journal of Chemical Physics
(2018)
149
Modelling Electron Transfers Using Quasidiabatic Hartree-Fock States
KT Jensen, RL Benson, S Cardamone, AJW Thom
Journal of chemical theory and computation
(2018)
14
Holomorphic Hartree–Fock Theory: The Nature of Two-Electron Problems
HGA Burton, M Gross, AJW Thom
Journal of Chemical Theory and Computation
(2018)
14
A study of the dense uniform electron gas with high orders of coupled cluster
VA Neufeld, AJW Thom
The Journal of Chemical Physics
(2017)
147
Stochastic coupled cluster theory: Efficient sampling of the coupled cluster expansion.
CJC Scott, AJW Thom
Journal of Chemical Physics
(2017)
147
An Open Reconfigurable Research Platform as Stepping Stone to Exascale High-Performance Computing
D Stroobandt, CB Ciobanu, MD Santambrogio, G Figueiredo, A Brokalakis, D Pnevmatikatos, M Huebner, T Becker, AJW Thom
PROCEEDINGS OF THE 2017 DESIGN, AUTOMATION & TEST IN EUROPE CONFERENCE & EXHIBITION (DATE)
(2017)
39
EXTRA: Towards the Exploitation of eXascale Technology for Reconfigurable Architectures
D Stroobandt, AL Varbanescu, CB Ciobanu, M Al Kadi, A Brokalakis, G Charitopoulos, T Todman, X Niu, D Pnevmatikatos, A Kulkarni, E Vansteenkiste, W Luk, MD Santambrogio, D Sciuto, M Huebner, T Becker, G Gaydadjiev, A Nikitakis, AJW Thom
2016 11th International Symposium on Reconfigurable Communication-centric Systems-on-Chip (ReCoSoC)
(2016)

Head of group

Research Interest Group

Telephone number

01223 336470

Email address

College