Octopus is a software package for density-functional theory (DFT), and time-dependent density functional theory (TDDFT).
The main developing team of this program is composed of:
- Alberto Castro (firstname.lastname@example.org)
- Angel Rubio (email@example.com)
- Carlo Andrea Rozzi (firstname.lastname@example.org)
- Florian Lorenzen (email@example.com)
- Heiko Appel (firstname.lastname@example.org)
- Micael Oliveira (email@example.com)
- Miguel A. L. Marques (firstname.lastname@example.org)
- Xavier Andrade (email@example.com)
Other contributors are:
- Sebastien Hamel
- parallel version of oct-excite.
- Eugene S. Kadantsev (firstname.lastname@example.org)
- Initial linear response code
Octopus is based on a fixed-nucleus code written by George F. Bertsch and K. Yabana to perform real-time dynamics in clusters  and on a condensed matter real-space plane-wave based code written by A. Rubio, X. Blase and S.G. Louie . The code was afterwards extended to handle periodic systems by G.F. Bertsch, J.I. Iwata, A. Rubio, and K. Yabana . Contemporaneously there was a major rewrite of the original cluster code to handle a vast majority of finite systems. At this point the cluster code was named tddft.
This version was consequently enhanced and beautified by A. Castro (at the time Ph.D. student of A. Rubio), originating a fairly verbose 15,000 lines of Fortran 90/77. In the year 2000, M. Marques (aka Hyllios, aka António de Faria, corsário português), joined the A. Rubio group in Valladolid as a postdoc. Having to use tddft for his work, and being petulant enough to think he could structure the code better than his predecessors, he started a major rewrite of the code together with A. Castro, finishing version 0.2 of tddft. But things were still not perfect: due to their limited experience in Fortran 90, and due to the inadequacy of this language for anything beyond a HELLO WORLD program, several parts of the code were still clumsy. Also the idea of GPLing the almost 20,000 lines arose during an alcoholic evening. So after several weeks of fantic coding and after getting rid of the Numerical Recipes code that still lingered around, Octopus was born.
The present released version has been completely rewritten and keeps very little relation to the old version (even input and output files) and has been enhanced with major new flags to perform various excited-state dynamics in finite and extended systems (one-dimensional periodic chains). The code will be updated frequently and new versions can be found here.
The main features of the present version are described in detail in octopus: a first principles tool for excited states electron-ion dynamics . Updated references as well as results obtained with octopus will be posted regularly to the octopus web page. If you find the code useful for you research we would appreciate if you give reference to this work and previous ones.
Contributing to Octopus
If you have some free time, and if you feel like taking a joy ride with Fortran 90, just drop us an email. You can also send us patches, comments, ideas, wishes, etc. They will be included in new releases of octopus.
If you found a have a bug, please report it to our Bug Tracking System: http://www.tddft.org/trac/octopus/newticket
The Octopus Copying Conditions
This program is “free”; this means that everyone is free to use it and free to redistribute it on a free basis. What is not allowed is to try to prevent others from further sharing any version of this program that they might get from you.
Specifically, we want to make sure that you have the right to give away copies of the program, that you receive source code or else can get it if you want it, that you can change this program or use pieces of them in new free programs, and that you know you can do these things.
To make sure that everyone has such rights, we have to forbid you to deprive anyone else of these rights. For example, if you distribute copies of the program, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must tell them their rights.
Also, for our own protection, we must make certain that everyone finds out that there is no warranty for this program. If these programs are modified by someone else and passed on, we want their recipients to know that what they have is not what we distributed, so that any problems introduced by others will not reflect on our reputation.
The precise conditions of the license are found in the General Public Licenses that accompany it.
Please note that Octopus distribution normally comes with some external libraries that are not covered by the GPL license, please see the Copying Appendix for the copying conditions or these packages.