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, and the Technical University of Denmark (DTU) in Copenhagen, Denmark.


Henrik Koch (NTNU)

Lead developers

S. D. Folkestad (NTNU), E. F. Kjønstad (NTNU), R. H. Myhre (NTNU), A. C. Paul (NTNU)


J. H. Andersen (DTU), A. Balbi (SNS), M. Castagnola (NTNU), S. Coriani (DTU), T. Giovannini (NTNU), L. Goletto (NTNU), T. S. Haugland (NTNU), A. Hutcheson (NTNU), I-M. Høyvik (NTNU), R. Matveeva (NTNU), T. Moitra (DTU), S. Roet (NTNU), E. Ronca (IPCF-CNR), M. Scavino (SNS), A. Skeidsvoll (NTNU), A. K. Schnack-Petersen (DTU), Å. H. Tveten (NTNU)

Funding and support

  • Norwegian University of Science and Technology (NTNU)

  • Scuola Normale Superiore (SNS)

  • Technical University of Denmark (DTU)

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

  • Marie Skłodowska-Curie European Training Network COSINE – COmputational Spectroscopy In Natural sciences and Engineering

  • Research Council of Norway – FRINATEK, projects 263110 and 275506.

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

How to cite eT

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),


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