The Genetic algorithm for structure prediction – GASP – predicts the structure and composition of stable and metastable phases of crystals, molecules, atomic clusters and defects from first-principles.  The GASP program is interfaced to many energy codes including: VASP, LAMMPS, MOPAC, Gulp, JDFTx and can efficiently run on parallel architectures.  For more information about the code and how to download, install and use it, see the GASP website: developers: William W. Tipton, Ben Revard, Stewart Wenner, Anna Yesypenko, and Richard G. Hennig


  • Structure and Stability Prediction of Compounds with Evolutionary Algorithms.
    B. C. Revard, W. W. Tipton, and R. G. Hennig. Topics in Current Chemistry 345, 181 (2014).
  • Prediction of Structures, Phase Stability and Electrical Potential of Li-Si Battery Anode Materials.
    W. W. Tipton, C. R. Bealing, K. Mathew, R. G. Hennig. Phys. Rev. B 87, 184114 (2013).
  • Ab initio based empirical potential used to study the mechanical properties of molybdenum.
    H. Park, M. R. Fellinger, T. J. Lenosky, W. W. Tipton, D. R. Trinkle, S. P. Rudin, C. Woodward, J. W. Wilkins, and R. G. Hennig. Phys. Rev. B 85, 214121 (2012).
  • Pressure-induced structure transitions in Eu metal to 92 GPa.
    W. Bi, Y. Meng, R. S. Kumar, A. L. Cornelius, W. W. Tipton, R. G. Hennig, Y. Zhang, C. Chen, and J. S. Schilling. Phys. Rev. B 83, 104106 (2011),
  • Emergent reduction of electronic state dimensionality in dense ordered Li-Be alloys.
    J. Feng, R. G. Hennig, N. W. Ashcroft and Roald Hoffmann. Nature 451, 445 (2008),


We implemented an implicit solvation model that describes the effect of electrostatics, cavitation, and dispersion on the interaction between a solute and solvent into the plane-wave DFT code VASP. Our implementation provides a computationally efficient means to calculate the effects of solvation on molecules and crystal surfaces. The strength of our solvation model implementation is its capability to handle large periodic systems such as metal and semiconductor surfaces and its interoperability with standard ultrasoft pseudopotential and projector-augmented wave potential libraries. The software is freely available as a patch to the original VASP code from our website:

Lead developers: Kiran Mathew and Richard Hennig


  • Implicit solvation model for density-functional study of nanocrystal surfaces and reaction pathways.
    K. Mathew, R. Sundararaman, K. Letchworth-Weaver, T. A. Arias, and R. G. Hennig. J. Chem. Phys. 140, 084106 (2014).
  • Accuracy of Exchange-Correlation Functionals and Effect of Solvation on the Surface Energy of Copper.
    M. Fishman, H. L. Zhuang, K. Mathew, W. Dirschka, and R. G. Hennig. Phys. Rev. B 87, 245402 (2013).


To describe heterogeneous solid/liquid materials interfaces we developed and implemented a new implicit solvation method for quantum Monte Carlo that avoids thermodynamic sampling or explicit solvent electrons. The method is based on a rigorous statistical treatment of the solvent and utilizes a variational theorem. The method is applicable to a variety of challenges in materials science ranging from transition states of solvated molecules to surface reactions in liquid environments. The method is implemented into the quantum Monte Carlo code CASINO and interfaced to the JDFTx package for generating the trial orbitals and solvation potential.

Lead developer: Katie Schwarz


  • A framework for solvation in quantum Monte Carlo.
    K. A. Schwarz, R. Sundararaman, K. Letchworth-Weaver, T. A. Arias, and R. G. Hennig. Phys. Rev. B 85, 201102(R) (2012), Selected as Editor’s Suggestion.


All our open source software development efforts have been moved to github.
Check us out on github at