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 researching prebiotic reaction networks and the original of chirality.

More information about my research and research group is available on the group website.

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 2026 are now open. Applications for scholarship funding have now closed, but applicants with external funding will still be able to apply until February 2026 (for MPhil) and May 2026 (for PhD). 
 

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

Folded Spectrum VQE : A quantum computing method for the calculation of molecular excited states
LC Tazi, AJW Thom
(2023)
Non-unitary Trotter circuits for imaginary time evolution
C Leadbeater, N Fitzpatrick, DM Ramo, AJW Thom
(2023)
A simple and efficient route towards improved energetics within the framework of density-corrected density functional theory
D Graf, AJW Thom
(2023)
A hybrid stochastic configuration interaction-coupled cluster approach for multireference systems
M-A Filip, AJW Thom
(2023)
Studies on the Transcorrelated Method
N Lee, AJW Thom
(2023)
The density and pressure of helium nano-bubbles encapsulated in silicon
NC Pyper, AJW Thom, CT Whelan
(2022)
Trade-Off between Redox Potential and the Strength of Electrochemical CO2 Capture in Quinones.
AT Bui, NA Hartley, AJW Thom, AC Forse
The Journal of Physical Chemistry C
(2022)
126
Trade-off between redox potential and strength of electrochemical CO2 capture in quinones
AT Bui, NA Hartley, AJW Thom, AC Forse
(2022)
Reducing unitary coupled cluster circuit depth by classical stochastic amplitude prescreening
M-A Filip, N Fitzpatrick, DM Ramo, AJW Thom
Physical Review Research
(2022)
4
Making the most of data: Quantum Monte Carlo postanalysis revisited.
T Ichibha, VA Neufeld, K Hongo, R Maezono, AJW Thom
Phys Rev E
(2022)
105

Research Group

Research Interest Group

Telephone number

01223 336470

Email address

College