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Curtin University


The official home of GULP is within the Curtin Institute for Computation at Curtin University, Perth, Western Australia, where the author Prof. Julian Gale is part of the Computational Materials and Minerals group.

The latest distributed version of the program is 6.1. However, earlier versions are also available for download too. Note that GULP is distributed as source code. However, version 4.3 is also available as a PC Windows exe (thanks to Damien Carter). NB: We accept no responsibility for the Windows exe!

Graphical interfaces to GULP from both Materials Studio and GDIS are available.

New features available in GULP6.1:
  • Universal force field of Spicher and Grimme added (GFN-FF)
  • Periodic version of GFN-FF (pGFN-FF) added
  • Equipartition free energies can now be used for fitting and optimisation
  • Output of input files for JDFTx added
  • Synchronous transit method added as a seperate approach
  • Valence bond potentials added
  • Thermodynamic integration added during MD
  • Support for Alamode version 1.3.0 added
  • Variable charges can now use diagonalisation in parallel
  • OpenMM taper function added
New features available in GULP6.0:
  • Rigid molecules added for optimisation and property calculation
  • Implementation of Tersoff potentials corrected and improved
  • Improvements and corrections to phonon calculation where analytic 2nd derivatives are not available
  • Modifications to handle gfortran version 10
  • Terse option extended to molecules
  • Output of polarisation added for finite difference calculation of piezoelectric constants
  • Sub-option added to change supercell order for Phonopy compatibility
  • Option added to fit the sum of core and shell gradients
  • Option to specify a dielectric constant added
  • Screened Coulomb potential added with a distant dependent dielectric
  • Support for PPP coarse-grained model added including Langevin damped polarisation
  • Interface to Alamode modified so that an external script can be used to run calculations for thermal conductivity
New features available in GULP5.2:
  • Multiple temperature ramps now allowed
  • GAFF and GAFF2 force field libraries added (charges need to be set by user)
  • ReaxFF parameters are now species dependent
  • Separate smoothing of lone pair and overcoordination energies added for ReaxFF
  • Finite strain derivatives added with respect to a reference cell
  • Energy/gradient shifts for Lennard-Jones epsilon-sigma form
  • Utility added to create Wulff construction from surface/line/corner edges
  • Second derivatives added for point dipolar polarisability for non-self-consistent case
  • Damping add for charge-dipole polarisation using the Tang-Toennies form as per Madden and Wilson
  • Shear force option added
  • Use of finite difference second derivatives now enabled for optimisation
  • Potentials added for Ising model
  • Domain decomposition enabled for general unit cells
  • Cray compilers now supported by mkgulp
New features available in GULP5.1:
  • Improved handling of parallel output
  • Interface to OpenKIM version 2
  • Automated interface to Alamode
  • Calculation of thermal conductivity using Boltzmann transport equations using Alamode
  • Multiple charge ranges added for electronegativity equalisation
  • Split bond electronegativity equalisation added
  • MEAM parameters extended and MEAM-2NN-QEq model added
  • Calculation of Grueneisen parameters added
  • Damping added to Becke-Johnson potential
New features available in GULP5.0:
  • Parallel second and third derivatives are now available
  • Smooth Particle Mesh Ewald has been added for MD
  • New phonon algorithm added with force constant supercells
  • Phonons at general k points now available for potentials without analytic 2nd dervatives
  • Faster finite difference algorithm added for some potentials
  • Numerous fixes and improvements
  • New mkgulp script provided to simplify compilation
New features available in GULP4.5:
  • Calculation of group velocities added
  • Interface to OpenKIM updated
  • Variables added as an option for LAMMPS files
  • 1-4 cutoff added for torharm potential/li>
  • UFF4MOF library updated
  • Options added to accelerate second derivatives for EAM/MEAM
  • Third derivatives added for bond-angle cross potentials
  • Library added for Si tersoff potential of Kumagi et al
  • Multiple Monte Carlo swap move added
  • Interface to PLUMED now uses version 2 instead of 1
New features available in GULP4.4:
  • Option for dummy lattice parameter in CIF files added
  • Option added to change the taper function for bond order potentials
  • Garofalini form of Stillinger-Weber 3-body potential added
  • Imaginary eigenvectors now used in projected densities of states
New features available in GULP4.3:
  • Extensive improvement of MEAM potentials
  • New parameter libraries added for MEAM-2NN potentials
  • ZBL potential added
  • Corrections to EDIP derivatives made
  • Fractional bond orders added
  • Iterative charge solver option added for COSMO
New features available in GULP4.2:
  • Option to compile with OpenKIM to provide energies and forces
  • Charges in EEM/QEq can be computed iteratively and in parallel
  • EQEq method added
  • Charges and NMR information can be computed using the Pacha method
  • Calculation of thermal conductivity added using Allen-Feldman formalism
  • Stability of adiabatic shell model MD improved
  • Raman susceptibilities can be computed and used for intensities
  • Molecular thermodynamics now includes rotation and translation
  • Eckart purification of molecular vibrations added
  • Non-analytic correction to phonons now handled for images of gamma point
  • Option to use control C to escape optimisation/fitting added
  • IR intensities now computed from Born effective charge tensor
  • Atomic stress calculation added
  • Fennell and Geletzer version of Wolf sum added
  • Custom bond types and ability for user to changed them added for UFF
  • Gaussian broadening added as an option for DOS plots
  • Version of UFF for MOFs added to libraries
  • Many other changes and improvements....
New features available in GULP4.0:
  • ReaxFF reactive force field added (analytical first derivatives only)
  • EDIP force field for carbon from Nigel Marks
  • Continuum solvation models added
  • Calculation of PDF data added by Beth Cope and Martin Dove
  • Fitting of bond lengths and angles added
  • Fitting of relative energies added
  • Many other changes and improvements....
New features available in GULP3.4:
  • Code now rewritten in f90 with fully dynamic memory
  • Location of files now set using environment variables
  • Gasteiger charges can be computed
  • Support for the Dreiding and Universal Force Fields added
  • Concept of bond order associated with bonds added
  • Force constant model added
  • Electric field option added
  • Keywords added to print out energy contributions
  • New EAM functions and densities added, including the Glue model
  • Calculation of meam phonon kinetic energies added
  • New MD integrator added for improved handling of NVT and NPT ensembles
  • Brenner potential can now be mixed with other models
  • Plane potentials added
  • Output of Biograf files added
  • New interatomic potentials added
New features available in GULP3.1:
  • Six-body potentials added
  • Hydrogen-bond three-body potential added
  • Inversion and squared inversion potentials added
  • Equatorial ESFF three-body potential added
  • Voter form of EAM potential added including ability to ready Paradyn files
  • EAM densities can now target specific species
  • Multiple EAM densities now allowed
  • Output of oscillator strengths added
  • Damping of frequency dependent properties allowed
  • Output of moment of inertia tensor added
  • Parallelisation of the EAM energy included, as well as for 1- & 2-D cases
  • Fitting comparison added to output
  • Fitting of stresses permitted
  • Masses can now be controlled for individual species
  • Continuation lines now allowed in libraries as well as option to read fitting flags
  • Numerical stability of defect calculations improved for small displacements
  • Partial occupancy handled in dipole correction energy
  • Angular taper function added
New features available in GULP3.0:
  • Calculations for 2-D periodic systems, surfaces and interfaces
  • Calculations for 1-D periodic systems, such as polymers
  • Monte Carlo calculations
  • Bond order potentials (Brenner 2003 and Tersoff forms)
  • LO/TO phonon corrections at the gamma point
  • New properties have been added including Born effective charges
  • Fully dynamic use of memory in Fortran 90 - sizes removed
  • Spatial decomposition algorithms for linear scaling with large systems
  • Output of CIF files added
  • Handling of tab characters in input added
  • Minimum three-body cut-off distances added
  • Specification of K vectors based on centred cell allowed for
  • Output of file formats for multiple configurations added
  • Overlaying of density functional forms added in EAM
Features new to GULP1.3 from GULP1.2 are:
  • Analytical derivatives of the free energy for 2-,3-,4- and many-body potentials
  • Parallelisation for molecular dynamics and conjugate gradients optimisation
  • Simulated annealing and structure prediction algorithms based on cost function added
  • Scaling of 1-4 interactions
  • Dynamic memory can be now be handled using f90, including for Linux
  • Refractive indices are now calculated as part of the properties
  • Option added to calculate screened Coulomb term in real space
  • Library of glass forcefield potentials added
  • Young's modulus and Poisson's ratio data now added to properties
  • Option to use the minimum image convention in MD of large systems added
Features new to GULP1.2 from GULP1.1 are:
  • NVT Nose-Hoover dynamics
  • NPT variable cell dynamics
  • shell model molecular dynamics
  • out of plane potential added
  • damped dispersion potential added
  • exponential breathing shell self term added
  • input of fractional coordinates allowed
  • library of Lewis and Catlow potentials now available
  • embedded atom model potentials (Sutton-Chen etc)
  • calculation of bulk modulus
  • neutralising charge background for charged unit cells
  • improved tuning of real/recip weighting factor
  • QEq charge equalisation scheme added
  • variable charges with first derivatives for opt and MD
  • calculation of the first derivatives of the charges for EEM and QEq
  • calculation of the second derivatives of the charges for EEM and QEq
  • heat capacity (Cv) and entropy added as observables for fitting
  • ESFF combination rules for Lennard-Jones potential now available
  • harmonic cosine three-body potential added
  • specification of keywords after first line now possible
  • output of XYZ files for visualisation in Molden now added
  • Murrell-Mottram potential added
  • the asymmetry parameter is now output after an EFG calculation