The eT program

eT is an electronic structure program written in the Fortran 2018 standard with focus on coupled cluster and multilevel methods. The program is open source under the GPLv3 license, easy to use, rigorously tested, and optimized for performance.

We are always looking for collaborators. If you wish to contribute, please visit the for developers page on the wiki.

The eT collaboration

eT is primarily developed by research groups at the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway, Scuola Normale Superiore (SNS) in Pisa, Italy, the Technical University of Denmark (DTU) in Copenhagen, Denmark and the Univerity of Perugia (UNIPG) in Perugia, Italy.


Henrik Koch


Sarai D. Folkestad

Eirik F. Kjønstad

Alexander C. Paul

Former maintainers

Rolf H. Myhre


Josefine H. Andersen

Sara Angelico

Alice Balbi

Alberto Barlini

Andrea Bianchi

Chiara Cappelli

Matteo Castagnola

Sonia Coriani

Sarai D. Folkestad

Tommaso Giovannini

Linda Goletto

Tor S. Haugland

Anders Hutcheson

Ida-Marie Høyvik

Eirik F. Kjønstad

Henrik Koch

Marcus T. Lexander

Torsha Moitra

Rolf H. Myhre

Gioia Marrazzini

Alexander C. Paul

Regina Paul

Jacob Pedersen

Matteo Rinaldi

Rosario R. Riso

Sander Roet

Enrico Ronca

Bendik S. Sannes

Marco Scavino

Anna Kristina Schnack-Petersen

Andreas S. Skeidsvoll

Jan Haakon M. Trabski

Åsmund H. Tveten

Current funding and support

  • Norwegian University of Science and Technology

  • Scuola Normale Superiore

  • Technical University of Denmark

  • UNINETT Sigma2 – the National Infrastructure for High Performance Computing and Data Storage in Norway

  • Research Council of Norway – FRINATEK, projects 275506, 2017-2023

  • Research Council of Norway – GCmolecule, projects 325574, 2022-2025

  • Independent Research Fund Denmark – Natural sciences, research project 2 no. 7014-00258B, 2018-2023

  • European Research Council – QuantumLight, project nr. 101020016, 2022-2027

  • European Research Council – QED-Spin, project nr. 101040197, 2023-2028

How to cite eT

Please cite the main papers describing the eT releases:

S. D. Folkestad, E. F. Kjønstad, R. H. Myhre, J. H. Andersen, A. Balbi, S. Coriani, T. Giovannini, L. Goletto, T. S. Haugland, A. Hutcheson, I-M. Høyvik, T. Moitra, A. C. Paul, M. Scavino, A. S. Skeidsvoll, Å. H. Tveten, and H. Koch, “eT 1.0: An open source electronic structure program with emphasis on coupled cluster and multilevel methods”, J. Chem. Phys. 152, 184103 (2020),

together with the specific publications for the methodologies used - see at the end of the output file.


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