ACES

Author

J.F. Stanton, J. Gauss, J.D. Watts, M. Nooijen, N. Oliphant, S.A. Perera, P.G. Szalay, W.J. Lauderdale, S.A. Kucharski, S.R. Gwaltney, S. Beck, A. Balkova, D.E. Bernholdt, K.K. Baeck, P. Rozyczko, H. Sekino, C. Hober, and R.J. Bartlett. Integral packages included are VMOL (J. Almlof and P.R. Taylor); VPROPS (P. Taylor) ABACUS; (T. Helgaker, H.J. Aa. Jensen, P. Jorgensen, J. Olsen, and P.R. Taylor).

Origin

ACES is a program product of the Quantum Theory Project, University of Florida.

Version

ACES II & ACES III version 2.7.0

Official Web Site

http://www.qtp.ufl.edu/ACES

Brief Program Description

ACES II is a modular program for ab initio calculations. The major strength of the program is treating electron correlation accurately by using methods based on many body perturbation theory (MBPT) and coupled cluster theory (CC). It also provides analytically evaluated NMR chemical shift tensors at the SCF and MBPT(2) level using GIAOs. New features in this version include TD-CCSD energies and analytical derivatives and Equation-of-Motion CCSD calculations of properties and excited states. The program's capabilities are:

• Single Point calculations

• Geometry Optimisations

• Vibrational Frequency calculations

• Excitation Energy calculation with EOM-CCSD

• NMR chemical shifts and spin-spin coupling calculations

• Hybrid Hartree Fock Density Functional Theory (HF-DFT) methods
  - Note: the HF-DFT keyword is no longer valid

• Time-dependent Hartree Fock calculations for obtaining properties, such as frequency-dependent polarizability calculations

• Effective Core Potentials

ACES III is the fully parallel successor to ACES II and it can compute HF-SCF, MBPT(2), and CCSD energies and gradients in parallel.

Areas of Application

• Program especially well suited for very accurate calculations where reliable treatment of electron correlation is necessary, such as in the case of chemical reactions.

• Calculation of equilibrium structures, and vibrational frequencies.

• Calculation of excited states.

• Calculation of magnetic and other molecular properties.

Implementation and Access

ACES II and ACES III version 2.7.0 are now available on Magellan and can be accessed as in the following example:

$CHEM/runaces progname inputfile [ save ]

where progname is aces2 or aces3 , inputfile is the name of a file containing the inputdata and is postfixed by .zmat in the current directory. The output will be returned to a file whose name is generated from datafile by stripping any suffix and appending .out . There is also an option called save which is used when files need saving for restarting large calculations.

Please refer to the man page for details on the environment settings needed (see below).

Machines

Available on Magellan.

Documentation

At present, there is no documentation for this version of the program. Users should refer to the draft version of the manual for version 2.7.0 which can be found in pdf format in the directory $CHEM/doc/aces27.

Example input files can be downloaded from the web page with benchmarks: http://www.qtp.ufl.edu/PCCworkshop/PCCbenchmarks.html

The manual can also be downloaded from the ACES website at: http://www.qtp.ufl.edu/ACES/docs.shtml

For details and examples on how to use ACES, please see the man page by typing: man runaces

Literature References

References on the general background and methods used are given in the program 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

A variety of Gaussian type basis sets are provided which was obtained through the Pacific Northwest National Laboratory (PNNL) and need to be acknowledged by users according to the citation outlined in the Manual.