The following features and enhancements have been introduced in Version 7.0 of the code:

### Changes to the functionality of the code

1. Fermi-dirac smearing implemented

Normally orbitals are filled according to a step function, but this can cause convergence problems if it is uncertain which state to converge on. Fermi smearing allows orbitals to be partially filled, which can improve convergence in some problematic cases.

2. Atomic Guess extended

It is now possible to specify the per-atom electron configuration or charge for the atomic guess. It is also possible to specify alpha and beta populations for atoms in UHF calculations.

3. Update of the Graphics Module

The graphics modules have been revised to enable both density and potential codes to drive through full (s,p,d,f,g) basis sets.

4. User-defined convergence schemes:

It is now possible for a user to specify a particular convergence scheme, rather than the default one within GAMESS-UK. This is activated by placing the convergence criteria within a block in the input file delimited by the keywords newscf and end, following the specification of the runtype.

This functionality is available in serial and within the parallel MPI ScaLAPACK driver.

5. Changes to the DFT Module
• New DFT Functionals

Several new functionals have been added:

• PBE exchange-correlation functional
• HCTH120, HCTH147, HCTH407, KT1 and KT2 functionals.
• PW92 local correlation functional
• PW91 exchange, correlation and exchange-correlation functionals.
• B95 meta-GGA correlation functional.
• BB95, B1B95 and BB1K meta-GGA functionals.

NB - for the meta-GGA functionals, only the energies and gradients can be calculated - the second derivatives of the energy are not available.

• More flexible DFT grid specifications

The atom size is used in a number of tests within in the DFT code. Previously the same size was used for all tests, however it is now possible to specify the atomic size for each test separately, as shown in the examples below:

1. The atomic radii for the angular grid pruning schemes: pradii 3.0

It is also now possible to specify the grid size for a row of the periodic table - previously this had to be done on a per-element basis. For example, to specify the grid size for the Lebedev-Laikov angular grid for the first row of the periodic table:

lebedev row 1 194

6. Changes to the Post-HF Modules
• The 255 basis function limit in the MRDCI code has been removed, so that the code is effecively open-ended in the number of basis functions permitted.
• Configuration Interaction Transformation between AO and MO basis' has been extended to g functions.
• A facility to allow the punching of both transformed integrals and CI coefficients from the full CI code has been introduced. This uses (i) the cards directive, and (ii) an extension of the current print facility within the Full CI module. Thus the data file:
    core 10000000
title
h2co - 3-21g basis - valence full-ci
super off nosym
cards trans fullci
zmatrix angstrom
c
o 1 1.203
h 1 1.099 2 121.8
h 1 1.099 2 121.8 3 180.0
end
active\5 to 22 end\core\1 to 4\end
runtype ci\fullci 18 4 4
punch 1 -8
enter



Would result in a complete list of transformed 1e- and 2e-integrals to the file moints.ascii and all ci coefficients (greater than 1 x 10-8) to the file civecs.ascii.

• The filenames for the files use in CI calculations can now be set through file directives in the input file as well as environment variables.
• MR-ACPF (Multireference Averaged Coupled-Pair-Functional), MR-AQCC (Multi-Reference Average Quadratic Coupled-Cluster) and the CEPA0 coupled electron-pair approximation methods have been added to the MRDCI module.
7. The use of the HARMONIC directive has been extended to the Valence Bond code, allowing spherical harmonic basis sets to be used for d, f and g functions.
8. A simple solvation model has been implemented in the Valence Bond code.
9. Arbitrary (not spinadapted) wavefunctions are now possible in the Valence Bond code.
10. The Valence Bond module can be compiled with 8-byte integers.
11. The RESTORE option has been added to the ZORA module to allow zora relativistic (atomic) corrections to be stored and restored on the current and foreign dumpfile. This permits easy restart calculations, when the ZORA corrections do not need to be recalculated.
12. New distributed data MPI HF/DFT driver

A distributed-data HF and DFT module has been developed using MPI-based tools such as ScaLAPACK. All data structures, except those required for the Fock build are fully distributed. The functionality of this code is currently limited to closed shell and unrestricted open shell. To build this code BLACS and ScaLAPACK ( available from www.netlib.org ), must be installed on the target machine and the mpi build option selected when configuring the code.

A taskfarming harness has been developed. This is an MPI program designed to be run on a large number of processors on a parallel machine and 'batch processes' numerous small GAMESS-UK jobs. The taskfarming harness is currently only available as a separate binary of the mpi build of the code and is selected by choosing the taskfarm keyword when configuring the mpi code.

### Changes to the structure of the code

1. New Ports The code has been ported to several new platforms:
• Macintosh OSX (G3, G4, and G5 processors)
• Windows XP
• AMD Opteron and Athlon processors running Linux.
• Intel Xeon, EM64T and Itanium processors running Linux.
• HP-UX running on Itanium processors.
• Sunfire v880 server
• SGI Altix
• Cray XD1
2. Global Arrays

The version of the Global Arrays supplied with GAMESS-UK has been updated from 3.3 to GA 3.4b.

3. MOPAC

The MOPAC code within GAMESS-UK has been updated to version 7.0

4. Configuring GAMESS-UK

A new configure process has been developed to ease porting the code to new platforms and making it easier for users to configure the build on their own machine. All platform-specific variables for the make process are stored in a file with an .mk suffix in the GAMESS-UK-7.0/config directory and the configuration process is run by the configure script in the main GAMESS-UK-7.0 directory. There are further notes in the file: GAMESS-UK-7.0/INSTALL.

5. Testing the parallel code

A new testing regieme has been developed for the parallel code. The testing regime is designed for users of the code who build from source and want to ensure that the code is functioning correctly. The test cases and README's explaining how to run the cases can be found in the directories:

GAMESS-UK-7.0/examples/parallel\_GAs

for the Global Array-based code and:

GAMESS-UK-7.0/examples/parallel\_MPI

for the new MPI HF/DFT module.

### Peripheral Changes

1. Demo Binaries

Free Windows, Macintosh and Linux demo versions are available for users who wish to try out the code.

2. GAMESS-UK Forum

A GAMESS-UK Forum has been added to the Distributed Computing forums run at Daresbury. You can find the Forum at:

www.cse.clrc.ac.uk/disco/index.shtml

Please use the forum to ask any general questions you may have about GAMESS-UK or to solicit tips from the developers and other users on the best way to run GAMESS-UK.

3. Changes to the website

The website has been updated and moved to a new url and a Bugzilla facility for logging and querying bugs with the code has also been added.

The new URL for the main GAMESS-UK website is:

www.cfs.dl.ac.uk

And the URL for the database of known bugs in the code is:

www.cfs.dl.ac.uk/cgi-bin/bugzilla/index.cgi
4. CCP1GUI

The CCP1GUI is a free, extensible Graphical User Interface to various computational chemistry codes. Although it has interfaces to other codes such as Dalton and Mopac, the CCP1GUI has been developed around GAMESS-UK and provides a powerful tool for setting up and viewing the results of calculations with GAMESS-UK.

The CCP1GUI is hosted on sourceforge at:

http://sourceforge.net/projects/ccp1gui/

The Python source code can be downloaded directly from Sourceforge, or there are packaged distributions of the CCP1GUI for different operating systems and architectures available via ftp from:

ftp://ftp.dl.ac.uk/qcg/ccp1gui

## G A M E S S - U K : Version 6.3

### Release Date : Q1 2002

The following features and enhancements have been introduced in Version 6.3 of the code:

• Multi-Reference Moller-Plesset Perturbation Theory: A size-consistent variant of Multi-Reference MP2 theory, popularized in its CASPT2 form by Roos et al., has recently been reported [1]. While not as efficient as the MOLCAS variant, the code offers some extra capabilities in addition to being strictly size consistent, e.g. no restriction to CAS wavefunctions and MR-MP3. This module is integrated into the direct-CI module of GAMESS-UK.

[1]  The Size Consistency of Multi-Reference Moller-Plesset Perturbation Theory, H.J.J. van Dam, J.H. van Lenthe, P. Pulay, Mol.Phys. 93, 431 (1998)

• Semi-direct Table-driven CI: An implementation of the direct Table-driven CI method, in collaboration with R.J. Buenker. This provides more extensive capabilities in the treatment of electronic spectra and related phenomena.
• Enhancements to the DFT module including:
• More flexible grid input.
• Additional DFT functionals (FT97, HCTH, B97 and B97-1 etc.)
• Optimisations to coulomb fit DFT code.
• Built-in DFT Orbital sets (DZVP, DZVP2 and TZVP) and Auxiliary Coulomb Fitting Basis sets (DGauss-A1 and -A2, DeMon and those due to Ahlrichs).
• Major changes to all ECP-related code, with re-writes of the integrals and derivatives code. This has sped the energy integrals by between 2-3, and the gradients by a factor of at least 5. Addition of 4 sets of ECPs to internal libraries, including;
• LANL2 (including all inner-valence TM ECPs etc to library; the original HW ECP's are now code-named lanl
• CRENBS and CRENBL (Christiansen et al Small- and Large-core ECPs)
• STRLC and STRLS (Stuttgart RLC and RSC sets)

All ECPs plus associated basis sets have been added for all elements.
• Modifications to enhance and extend usability of the code, including;
• Section numbers for vectors/enter can now be omitted.
• Reduced functionality build options (SCF+DFT and MP2) for use on parallel machines with limited node memory, and for benchmark porting exercises.
• Global Array and Peigs source for parallel builds has been updated, supporting a wider range of platforms.
• New Ports, including:
1. Linux PowerPC
2. Windows95
3. Parallel version for Alpha/Linux clusters
4. 64-bit build supported on a range of platforms (Origin, Alpha Linux, AIX, Solaris)
• Ability to read in Hessian information under runtype optx.
• Ability to use include directive in input files.
• NBO analysis extended to UHF wavefunctions. Interface provided to Bader's AIMPAC code.
• Alpha release of newscf module allowing more flexible treatment of cases showing poor SCF convergence.
• Reduction in memory usage for systems with many nuclear centres, e.g. for QM/MM studies.
• Work on CHARMM interface code.
• Graphical User Interfaces to the code:
• Using MOLDEN to prepare Z-matrices and to start simple interactive jobs. At present MOLDEN can process data from the GAMESS-UK output file, displaying optimised structures, orbitals and frequencies.
• A range of tutorial material has recently been developed as part of the Daresbury Code Workshop held at the Laboratory from 26-28 November, 2001. This included both tutorial and practical sessions dedicated to GAMESS-UK, and is available in both html and PDF

## G A M E S S - U K : Version 6.2

### Release Date : Q1 1999

The following features have been released in Version 6.2 of the code:

• Solvation and Embedding: The Direct Reaction Field (DRF) module for Solvation and Embedding, due to P. van Duijnnen and A. de Vries, originally developed within the HONDO programme.
• The DRF model, developed at the University of Groningen [1,2] is an embedding technique enabling the computation of the interaction between a quantum-mechanically described molecule and its classically described surroundings. The classical surroundings may be modelled in a number of ways, (i) by point charges to model the electrostatic field due to the surroundings (ii) by polarizabilities to model the (electronic) response of the surroundings (iii) by an enveloping dielectric to model bulk response (both static and electronic) of the surroundings, and (iv) by an enveloping ionic solution, characterized by its Debye screening length

The four representations may be combined freely to model all aspects of the surroundings. The best results with this model for solvation studies have been obtained by immersing the QM solute by 2-3 layers of explicitly described (point charges and polarizabilities) solvent molecules, enveloped by a surface defining the boundary between the microscopic system and a dielectric with bulk-solvent properties (dielectric constant). The model has also been applied to active sites in proteins.

Having decided on the QM system and the representation of the surroundings, the embedding may be treated at a number of levels:

1. electrostatic potential as a perturbation: The QM density is calculated as if the QM system were in vacuum. The interaction with the point charges is then calculated with the vacuum density.

2. electrostatic potential and reaction field as a perturbation: The QM density is calculated as if the QM system were in vacuum. The interaction with the point charges, polarizabilities, and dielectric is then calculated with the vacuum density.
3. electrostatic potential self-consistently: The QM density is calculated in the presence of the potential generated by the point charges by including this field in the one-electron hamiltonian.
4. electrostatic potential self-consistently and reaction field as a perturbation: The QM density is calculated in the presence of the potential generated by the point charges by including this field in the one-electron hamiltonian. The interaction with the polarizabilities and dielectric is then calculated with this density.
5. electrostatic potential and reaction field self-consistently: The QM density is calculated in the presence of the potential generated by the point charges, and the reaction field due to induced dipoles at the polarizabilities and surface polarization at the dielectric boundary, by including these fields in the one- and two-electron parts of hamiltonian, and Fock-matrix, respectively.
6. For many systems, the difference in total energy between the fourth and fifth levels is small; the self-consistent treatment of the electrostatic field is often found to change results substantially from a fully perturbative treatment.
7. [1]  A.H. de Vries, P.Th. van Duijnen, A.H. Juffer, J.A.C. Rullmann, J.P. Dijkman, H. Merenga, and B.T. Thole, J. Comput. Chem. 16 (1995) 37 and 16xx;

[2]  P.Th. van Duijnen and A.H. de Vries, Int. J. Quant. Chem., 60 (1996) 1111

• Hybrid QM/MM: An interface to the CHARMM QM/MM code, in collaboration with B. Brooks and E. Billings, of the NIH.
• The ZORA Relativistic Approximation: The ZORA (Zeroth Order Relativistic Approximation [1]) is a two component alternative to the full 4 component Dirac equation. While being much cheaper than the latter, it recovers a large part of the relativistic effects. We have implemented the scalar (1-component) form in GAMESS-UK and test calculations are underway [2]. The full 2-component implementation (including spin-orbit coupling) is in progress. The current implementation will allow all usual Ab Initio (and DFT) methods to be performed, including the major relativistic effects. This work is in collaboration with Prof. J.G. Snijders, Groningen.
• [1]  Ch Chsng, M. Pelissier, Ph. Durand, Phys. Scr. 34 (1986) 394

[2]  The Zora formalism applied to the Dirac-Fock equation, S. Faas , J.G. Snijders, J.H. van Lenthe, E. van Lenthe, E.J. Baerends, Chem.Phys. Lett. 246 (1995) 632.

• DFT Module: A production quality release of the CCP1 DFT module.

## G A M E S S - U K : Version 6.1

### Release Date : October 1997

The following features were made available in Version 6.1 of the code:

• An initial release of the Density Functional Module developed under the auspices of the Collaborative Computational Project, CCP1. Present functionality includes energies and gradients for closed and open shell systems, with B3-LYP, BLYP and LDA functionals.
• A variety of features to augment present capabilities for treating excited states. These included both conventional and direct-RPA (random phase approximation) calculations of transition energies and oscillator strengths, and a MCLR (Multi-configurational Linear Response) module (C. Fuchs, V. Bonacic-Koutecky and J. Koutecky, J.Chem.Phys. 98 (1993) 3121)
• The calculation of molecular properties was extended to include f-function basis sets. An interface was also provided to the Bader Analysis codes.
• The range of ECPs available were significantly extended, following the work of Cundari and Stevens. These included ECPs and associated bases sets for the Lanthanides (T.R. Cundari and W.J. Stevens, J. Chem. Phys. 98 (1993) 5555)
• Recent additions to the built-in basis set libraries within GAMESS-UK include the generally contracted basis sets due to Dunning and co-workers (cc-pvdz, pvtz, pvqz and pv5z etc)
• The original limitation to cartesian basis sets was extended through the provision of spherical harmonic basis sets for all options within the programme.
• Open shell Direct-SCF treatments for ROHF, UHF and GVB wavefunctions.
• An increase in the range of parallel platforms available to GAMESS-UK included implementations for the Cray T3E-900 and Cray T3E-1200, IBM SP/P2SC-160, Hitachi SR2201, Silicon Graphics Origin-2000 and DEC-8400/5.
• A significant effort was made to enhance the quality of user documentation and support. This included:
• hypertext pages
• email discussion lists featuring fellow GAMESS-UK users.

## G A M E S S - U K : Version 5.2

### Release Date : Marc 1996

The following features are available in Version 5.2 of the code:

1. The range of ECPs available are significantly extended, following the work of Cundari and Stevens. These include ECPs and associated bases sets for the Lanthanides (T.R. Cundari and W.J. Stevens, J. Chem. Phys. 98 (1993) 5555)
2. A variety of features are introduced to augment present capabilities for treating excited states. These include both conventional and direct-RPA (random phase approximation) calculations of transition energies and oscillator strengths, and a MCLR (Multi-configurational Linear Response) module (C. Fuchs, V. Bonacic-Koutecky and J. Koutecky, J.Chem.Phys. 98 (1993) 3121)
3. The treatment of correlation energy is enhanced through the inclusion of coupled cluster CCSD and CCSD(T) capabilities, due to Rendell and co-workers (T.J. Lee, A.P. Rendell and P.R. Taylor, J. Chem. Phys. 94 (1990) 5463)
4. A significant effort has been made to enhance the quality of user documentation and support. This includes:
5. Man pages and hypertext pages
6. email discussion lists featuring fellow GAMESS-UK users.
7. Open shell Direct-SCF treatments for ROHF, UHF and GVB wavefunctions are now available.

Users wishing to acquire the present release of the code should contact CFS via the contact details as listed on the How to contact CFS page. We would certainly appreciate input on the priority and demand for the development areas above.