Dalton

Author

Celestino Angeli, Keld L. Bak, Vebjoern Bakken, Ove Christiansen, Renzo Cimiraglia, Sonia Coriani, Paal Dahle, Erik K. Dalskov, Thomas Enevoldsen, Berta Fernandez, Christof Haettig, Kasper Hald, Asger Halkier, Hanne Heiberg, Trygve Helgaker, Hinne Hettema, Hans Joergen Aa. Jensen, Dan Jonsson, Poul Joergensen, Sheela Kirpekar, Wim Klopper, Rika Kobayashi, Henrik Koch, Andrea Ligabue, Ola B. Lutnaes, Kurt V. Mikkelsen, Patrick Norman, Jeppe Olsen, Martin J. Packer, Thomas B. Pedersen, Zilvinas Rinkevicius, Elias Rudberg, Torgeir A. Ruden, Kenneth Ruud, Pawel Salek, Alfredo Sanchez de Meras, Trond Saue, Stephan P. A. Sauer, Bernd Schimmelpfennig, K. O. Sylvester-Hvid, Peter R. Taylor, Olav Vahtras, David J. Wilson, Hans Agren

The above list must be acknowledged in any publication arising from work using this program.

Origin

Department of Chemistry, University of Oslo, Norway.

Version

Dalton 2.0

Official Web Site

http://www.kjemi.uio.no/software/dalton/dalton.html

Brief Program Description

This version of the Dalton program carries out accurate ab initio electronic structure calculations, using supplied data. The methodology currently available includes RHF, MP2, CI (CAS and RAS) and MCSCF (CASSCF AND RASSCF). The calculations can be for both closed- and open-shell molecules. A variety of molecular properties can be computed using a large built-in basis set library; these include vibrational analysis, magnetic properties as well as molecular response funtions (linear, quadratic and cubic response calculations, computations of spherical multipole moments and hyperfine coupling elements). A number of tools are also provided for pre- and post-processing. New features include Complete Integral-Direct Coupled Cluster calculations, Second-Order Polarization Propagator Approach (SOPPA) and Magnetic Circular Dichroism.

The program's capabilities are:

• Single point calculations and geometry optimisations

• Calculations of molecular vibrations and rotations

• Calculations of magnetic properties

• Calculations of electric properties

• Calculations involving solvent incorporation

• Calculations of optical and Raman properties

• Calculation of excitation energies

• Finite field calculations

• Production of output for graphical analysis

• Parallel execution using up to four processors

Additions to Dalton 2.0 include DFT implemented up to quadratic response theory for a wide variety of properties such as molecular Hessians and magnetic-resonance parameters. Also available is the NEVPT2 approach for calculating accurate energetics of multireference systems and the expli- citly correlated MP2-R12 method. There are also some changes to the way that data can be input to the program, in particular the molecule file is now keyword driven and contains no fixed-format input lines inless the basis set is explicitly given in the input file. It is now also possible to combine the molecule and control files into a single input file. For more details and a full listing of the new features available in Dalton 2.0 please see the user manual which can be downloaded from the web or found in $CHEM/doc/dalton2.0/dalton20manual.pdf

Areas of Application

• Calculation of potential energy surfaces

• Calculation of spectroscopic properties

• Direct dynamics calculation

• Calculation of properties of molecules in excited states

Implementation and Access

Dalton is available on Magellan and can be accessed as in the following example:

$CHEM/rundalton [options] dalfile molfile

where dalfile is the file for the description of the type of run requested. This file (called DALTON.INP in the Manual) needs to be post-fixed by .dal and should reside in the current directory. The description includes data for each part of the calculation under a number of major headings, such as **GENERAL, **INTEGRALS, **WAVE FUNCTIONS, **PROPERTIES and **RESPONSE and others.

The molecule file molfile above, is for the decription of data specific to the molecule of interest, including the geometry, basis set, charge, multiplicity, etc.. The molecule file should be postfixed by .mol and should also reside in the current directory.

The rest of the optional input files provide auxiliary information to specific parts of the program, all of which should be in the current directory. Output from the run will have the name of the .dal file by removing the trailing suffix and appending .out, unless the user specifies the preferred extension via a specific option (see below).

Dalton can be executed in parallel, for parallel execution procedures, please refer to the documentation and man page (see below).

Machines

Available on Magellan.

Documentation

A Unix-style man page is available online, gives a summary of the implementation and the options available for the program, accessible by typing: man rundalton. Detailed documentation is provided from the directory $CHEM/doc/dalton2.0 as a PDF file for printing at the user's own site. The PDF file may also be viewed online by using the acrobat reader facility on Magellan. An online documentation is available from the Dalton web site.

Literature References

References on the general background and methods used are given in the Dalton Reference Manual.

Specialist Support

Dr Helen Tsui. Address: Department of Chemistry, Imperial College London, South Kensington, London SW7 2AZ. Tel: 020 7594 1220 Email: helen.tsui@imperial.ac.uk.

Program Restrictions and Comments

N/A