Firefly 8.0.0 manual Version 2013-11-12 Table of Contents Introduction About this manual Overview of capabilities Firefly and GAMESS (US) Release history Citing Firefly Installing and running Firefly General information Windows Windows MPI implementations Windows and CUDA Linux Linux MPI implementations Linux and CUDA Installing Firefly on 64-bit Linux cluster with InfiniBand network and Intel MPI Command line options Creating an input file Input file structure Chemical control data Computer related control data Formatted input sections Input checking Input preprocessing Performance Introduction 64-bit processing support The P2P communication interface The XP and extended XP parallel modes of execution Utilizing HyperThreading CUDA The Fastdiag dynamic library Fast two-electron integrals code Quantum fast multipole method Output Main output The PUNCH file The IRCDATA file The MCQD files - 1 - Restart capabilities Coordinate types Introduction Cartesian coordinates Z-Matrix and natural internal coordinates Delocalized coordinates Utilizing symmetry Isotopic substitution Basis sets Introduction Built-in basis sets Using pure spherical polarization functions Using an external basis set file Manually specifying a basis set Using effective core potentials Partial linear dependence in a basis set Basis set superposition error (BSSE) correction Starting orbitals General accuracy switches Semi-empirical methods Introduction Available methods Hartree-Fock theory Introduction Restricted Hartree-Fock Unrestricted Hartree-Fock Restricted-open Hartree-Fock Direct vs conventional Convergence options General valence bond Introduction Open-shell SCF with GVB True GVB perfect pairing runs The special case of TCSCF A caution about symmetry Møller-Plesset correlation corrections Introduction MP2 calculations Performance of the MP2 code MP3 and MP4 calculations Density Functional Theory Introduction Available functionals Making modifications to functionals Empirical dispersion correction (DFT-D) - 2 - Time-Dependent Theories General information Excited state calculations with TDHF (RPA) Excited state calculations with TDDFT Configuration Interaction methods Introduction CI singles Higher-order CI Multi-configurational SCF methods Introduction Orbital optimization options Determinants vs CSFs Determinant CI code (ALDET) CSF CI code (GUGA) Performance Performing state-specific MCSCF calculations Performing state-averaged MCSCF calculations MCSCF state-tracking Strategies for selecting an MCSCF active space Multireference configuration interaction (Extended) Multi-configurational quasi-degenerate perturbation theory Introduction Overview of MCQDPT The XMCQDPT theory XMCQDPT vs XMS-CASPT2 Useful hints and best practices References Geometry optimizations Introduction Optimizations towards a minimum The Hessian Optimizations towards a transition state Optimizations and symmetry Mode following Constrained optimization Locating Conical Intersections (CIs) and Interstate Crossings (ISCs) Using numerical gradients Non-gradient total energy minimizations Hessian calculations General information Vibrational data Thermochemistry Raman activities Potential energy surface scans Rigid PES scans Relaxed PES scans - 3 - Reaction coordinate scans Intrinsic reaction coordinate Dynamic reaction coordinate Gradient extremal following Solvation models Self-consistent reaction field Polarizable continuum model Effective fragment potentials Calculating single geometry properties Introduction Electrostatic moments, electrostatic potential, electron density, electrostatic field, and electric field gradient Cube files Radiative transition moment Polarizabilities Spin-orbit coupling Stone's distributed multipole analysis Additional capabilities Orbital localization The NBO program Morokuma energy decomposition Interfacing with other programs Keyword list - 4 - Introduction About this manual The goal of this manual is to provide users with a description of all capa- bilities of the Firefly QC software package. It consists of two parts: a multi-chapter document that describes Firefly’s core functionality and a list of all keywords that are available in Firefly. The main document provides an overview of all important functionality pre- sent in Firefly. It deals with several theories and calculation types and, in addition, explains also how to set up Firefly in both Windows and Linux environments. It is intended for users new to Firefly (or new to a specific feature in Firefly) and assumes a basic to moderate level of QC knowledge. However, as this document contains several tips, users with a higher level of knowledge might also find this document useful. Note that as only an overview of Firefly’s functionality is provided, many of the less important (but not necessarily less useful) keywords are not discussed here. Instead, these can be found in the list of keywords. The list of keywords provides a complete listing of all options accessible in Firefly. This document contains very specific information for each fea- ture in Firefly and will foremost be useful to the more experienced users. However, beginning users are also encouraged to read through the list – they might come across some useful keywords not mentioned in the main docu- ment. In the list, keywords are organized by the keyword group (e.g. $CON- TRL, $SYSTEM, etc.) they belong to. The list is also available as a sepa- rate PDF document for the quick lookup of keywords. This manual is freely available from the Firefly website and falls under the copyright policy of the Firefly website. It may not be printed or re- published without the explicit permission of the copyright holder. Overview of capabilities The table below summarizes the current main capabilities of Firefly: Wavefunction RHF UHF ROHF GVB MCSCF Semiempirical SCF dm dm dm dm - SCF energy cdp cdp cdp cdp cdp SCF analytical gradient cdp cdp cdp cdp cdp SCF analytical Hessian cdp* - cdp* cdp* - DFT energy cdp cdp cdp - - DFT analytical gradient cdp cdp cdp - - CIS energy cdp - - - - - 5 - CIS analytical gradient cdp - - - - TDHF (RPA) energy cdp - - - - TDDFT energy cdp - - - - MP2 energy cdp cdp cdp - cdmp MP2 analytical gradient cdp - - - - MP3 energy cdm - - - - MP4 energy cdmp* - - - - CI energy cdp - cdp cdp cdp CI analytical gradient cd* - - - - Legend: c - conventional d - direct/semidirect m - multithreaded p - parallel * - additional notes: - CI analytical gradients and SCF analytical Hessians are programmed for spd basis sets only (note that CIS gradi- ents are available for any supported basis sets); - For GVB, SCF analytical Hessians are available only for a selected subset of possible GVB-type wavefunctions; - The MP4(SDQ) code is multithreaded but not parallel while the MP4(SDTQ) code is both multithreaded and paral- lel for (T) part. Firefly and GAMESS (US) Due to historical reasons, Firefly and GAMESS (US) share a lot of function- ality. When the Firefly project started in 1993 at MSU, it was based on the source code of the GAMESS (US) package developed by members of Mark Gor- don's group at ISU. Modifications to the source code were made by Alex Granovsky (who at that time was working at MSU), and the modified package was known as “PC GAMESS”. Initially, PC GAMESS was only available locally at MSU, but in 1997 it became available outside of MSU as part of the pub- lic GAMESS (US) distribution. Up until 1999, features added to GAMESS (US) were also incorporated in PC GAMESS. The latest release of GAMESS (US) of which the source code was used is the October 25th, 1999 release. After this release, the development of PC GAMESS and GAMESS (US) became independent. However, PC GAMESS did remain part of the GAMESS (US) distribution and a certain degree of compatibility between the two packages was maintained. With the release of version 7.1.C in 2008, PC GAMESS became completely forked from GAMESS (US) as an inde- pendent package and the name was changed to “Firefly” (though the PC GAMESS name was also used till the release of version 7.1.G). An overview of similarities and differences between Firefly and GAMESS (US) is given below. Similarities with GAMESS (US) Firefly supports all functionalities of GAMESS (US) up to the October 25th, 1999 release of GAMESS (US). Many additional features added to GAMESS (US) - 6 - since 1999 are supported as well. Ab initio SCF wavefunctions for RHF, UHF, ROHF, GVB and MCSCF cases are available. Correlation corrections include configuration interaction (CI) and Møller-Plesset (MP) perturbation theory. For MCSCF wavefunctions, correlation corrections can be calculated with MCQDPT2. Excited electronic states can also be described with configuration interaction with singles (CIS), RPA (i.e. TDHF), and TDDFT. Support for effective core potentials and a variety of density functional (DFT) func- tionals is available. Geometry optimizations can be performed with analyti- cal gradients at the HF, MP2, CI, DFT, and MCSCF levels. Analytical Hessi- ans can be computed for RHF, ROHF and GVB wavefunctions while numerical Hessians are available for all methods that support analytic gradients. Finally, numerical gradients and double-numerical Hessians are available for all methods. Differences with GAMESS (US) Firefly provides fast and efficient algorithms for Møller-Plesset second, third, and fourth order energy corrections. The DFT code in the Firefly is completely different with respect to that of GAMESS (US) and the two pro- grams support different density functionals. In Firefly, MCSCF gradients can be calculated semi-numerically