Introduction to the Firefly

What is Firefly?

Firefly (previously known as the PC GAMESS) is a freely available ab initio and DFT computational chemistry program developed to offer high performance on Intel-compatible x86, AMD64, and EM64T processors. Firefly package is being developed by the Firefly Project Team. The project coordinator and leading developer is Dr. Alex A. Granovsky. A number of other researchers have made significant contributions to the project over last years, especially those of Drs. Anastasia V. Bochenkova and James W. Kress are to be mentioned.

The project was launched in 1994. Initially, it was named "the PC GAMESS" and was based on the GAMESS (US) source code of ISUQCG (versions of up to October 25, 1999), while extending its functionality in many important areas. However, since 1999, no part of the GAMESS (US) was incorporated into the PC GAMESS, nor will it be added in the future, as the development of the PC GAMESS (now Firefly) became completely independent of the GAMESS (US) development. Nevertheless, the high-level compatibility of input and output files between these two packages was enforced to as much extent as possible for different programs.

However, until very recently (fall 2008), due to its historical roots, the package name was "PC GAMESS", and it was distributed as the part of GAMESS (US) distribution from the ISUQCG web site. As of Autumn 2008, the Firefly Project Team, as well as Firefly itself are no longer associated with GAMESS (US) and ISUQCG group. Starting December 4, 2009, the only valid name for the former PC GAMESS package is the "Firefly" one.

Design Philosophy for Speed

Initially, all time-critical sections of the legacy GAMESS (US) code were modified to achieve the maximum possible performance. Over time, almost all of legacy parts were rewritten from the scratch or completely replaced by the much more efficient code developed by the Firefly team. At moment, Firefly includes no more than 5-10% of the legacy code.

Furthermore, very efficient assembler-level libraries, both self-made and those provided by vendors like Intel's MKL are used throughout. Most of the Firefly source code is compiled by the set of several high-quality Fortran and C compilers (in particular, Intel Compilers vv. 6.0-9.1), while very flexible but somewhat outdated Watcom Fortran 77 compiler v. 11.0 is used primary as a glue to compile the rest of the sources and to link all the different style object modules and libraries together to produce the working Firefly binaries.

Design Philosophy for Features

Firefly has been constantly being developed to incorporate new functionality, improve performance, and extend existing features. For example, Firefly uses real time data compression/decompression, efficient modern algorithms of 2-e integral evaluation for direct calculation methods, very efficient MP2 energy and energy gradient modules, very fast RHF MP3/MP4 energy code, and state-of-the-art DFT, TDDFT, MCSCF, MRMP2, MCQDPT, and XMCQDPT implementation. Firefly runs parallel on SMP systems, clusters of computers, or both; with special attention paid to good scalability even on large clusters and many-core systems.

How to obtain Firefly

Firefly is freely available for all main PC operating systems: various Windows versions (Windows 7, 2008, Vista, 2003, XP, 2000, NT, 98/Me), OS/2, and even for ancient DOS (using Phar Lap|386 DOS-extender). There are also several different native Linux distributions of Firefly linked with various MPI implementations available for this OS. And now, by popular demand, Firefly runs under Mac OS X/Intel as well!

The latest Windows/Linux Firefly binaries are directly available from the Downloads section of the Firefly web server. Mac OS X/Intel distribution files can be found on our Firefly for MAC OS X page. Firefly version 8.0.0 prerelease binaries can be found on our beta test pages

• There exist various Firefly binaries specifically optimized for each particular type of modern Intel-compatible processors. First, you should decide what Firefly binaries you actually need. See the Firefly/PC GAMESS FAQ, question # 1, for information on this topic. Download the most appropriate zip archive with binaries from Downloads section of this server.
• After decompressing zip archive, you will get several files, including the "readme.txt" file which contains further instructions. In brief, you must read and agree with the terms of the Firefly License Agreement and send us some basic information on you and your computer system. Upon successful registration, you will get the key which can be used to extract Firefly binaries from the rar archive, which is the part of Firefly binary distribution package.
• Finally, familiarize yourself with both the common and Firefly-specific documentation, which is included into Firefly distribution. Various documents explaining features and keywords unique to Firefly are found in the Firefly manuals documents. Read the Firefly/PC GAMESS FAQ on installation and usage-related topics. If you prefer a graphical front end, check out Luceat and RUNpcg by Prof. Ernst Schumacher, FiCo (Firefly Commander) batch job processor for Firefly and PC GAMESS/Firefly by Dr. Pasquale Morvillo (available for direct download from the Downloads section), Facio by Dr. Masahiko Suenaga, and ChemCraft by Dr. Grigoriy Zhurko.

    Alex A. Granovsky, Firefly version 7.1.G, www http://classic.chem.msu.su/gran/firefly/index.html

This reference should be explicitly given in the appropriate section of your paper just like any other regular references are. Specifically, this should not be just a reference given in pass within the main body of paper. The recommended form of citation is as follows:

    Firefly QC package [1], which is partially based on the GAMESS (US) [2] source code.

1.     Alex A. Granovsky, Firefly version 7.1.G, www http://classic.chem.msu.su/gran/firefly/index.html

2.     M.W.Schmidt, K.K.Baldridge, J.A.Boatz, S.T.Elbert, M.S.Gordon, J.H.Jensen, S.Koseki, N.Matsunaga, K.A.Nguyen, S.Su, T.L.Windus, M.Dupuis, J.A.Montgomery J.Comput.Chem. 14, 1347-1363 (1993)

As of December 4, 2009, the support of any Firefly, PC GAMESS/Firefly, and PC GAMESS versions earlier than the Firefly version 7.1.G was abandoned and all the corresponding user licenses were terminated. Therefore, users of the outdated PC GAMESS, PC GAMESS/Firefly, or Firefly binaries (version 7.1.F and all earlier versions of Firefly or PC GAMESS/Firefly, and older PC GAMESS releases) are required to discontinue their use of the PC GAMESS/Firefly or PC GAMESS and upgrade to Firefly 7.1.G or 8.0.0 RC.