EXAT - EXcitonic Analysis Tool

EXAT is a tool developed by the Molecolab group at the Department of Chemistry, University of Pisa, Italy. For the other Molecolab tools please visit the website http://molecolab.dcci.unipi.it/software.html

EXAT is written in python. It is designed to compute the excitonic properties of a multichromophoric system and to simulate absorption and circular dichroism spectra.

The program itself is divided into two executables, and a few modules; the executables are:

• exat.py: the program that computes the excitonic properties

• spectrum.py: the program that computes the linear absorption and circular dichroism spectra from the output of exat.py

Disclaimer and copyright:

EXAT is Copyright (C) 2014-2024 L. Cupellini, S. Jurinovich, C.A. Guido, and B. Mennucci

The terms for using, copying, modifying, and distributing EXAT are specified in the file LICENSE.

Contacts:

Lorenzo Cupellini

lorenzo.cupellini@unipi.it

Dipartimento di Chimica e Chimica Industriale

Via G. Moruzzi 13, I-56124 Pisa PI, Italy

Documentation:

The main documentation for EXAT usage is in doc/ There is also a limited help for commands:

    exat.py -h
    spectrum.py -h

Some examples of usage can be found in examples/

System Requirements:

The program has been tested with the following configuration on linux systems:

• python version 2.7.2, 2.7.17, 3.7.7
• numpy version 1.9, 1.16, 1.21
• scipy version 1.7.3 (*)
• matplotlib version 2.2.3, 3.2.2 (*)(**)

(*) Only needed to run spectrum.py (**) Only needed for live spectrum plotting

Please, run tests to check your system compatiblity. Note that the GUI will only work with python3

Installation and Testing:

Once verified the system requirementsi, the executables exat.py and spectrum.py can be directly run.

You may add the src/ directory to your PATH, or link exat.py and spectrum.py in your bin/ directory.

To run tests go to tests/ and run

$ make

Check carefully the POSSIBLE FAILURE indications. A sign change in the exciton coefficients is not a problem.

Program's citation:

Please cite this program as:

S. Jurinovich, L. Cupellini, C.A. Guido, B. Mennucci, "EXAT - EXcitonic Analysis Tool", J. Comput. Chem. 2018, 39, 279-286, DOI: 10.1002/jcc.25118

Reference papers:

Please cite the following papers.

S. Jurinovich, G. Pescitelli, L. Di Bari, B. Mennucci, PCCP, 2014, 16, 16407-16418 (doi: 10.1039/c3cp55428g)

S. Jurinovich, C. A. Guido, T. Bruhn, G. Pescitelli, B. Mennucci, ChemComm, 2015, 51, 10498-10501 (doi: 10.1039/C5CC03167B)