Paper: A. I. Boothroyd, P. G. Martin, W. J. Keogh, and M. R. Peterson 2001, "An Accurate Analytic H4 Potential Energy Surface", J. Chem. Phys., in press: as a gzip'd PostScript file bmkp01.ps.gz (1.2 Mb, expands to 4.3 Mb), or as a PDF file bmkp01.pdf (1.7 Mb).

• See the text file README.TXT (6 kb) for a list of the available Appendices, Fortran programs, and data. These can be downloaded from this website using the links listed below, and also will soon be available from EPAPS (the electronic archive of the AIP).
• The Appendices to the above paper: as a gzip'd PostScript file bmkp01epaps.ps.gz (0.15 Mb, expands to 0.63 Mb), or as a PDF file bmkp01epaps.pdf (0.43 Mb).
• H4 Fortran program:
  • the text file h4progREADME.txt (4 kb) describing the BMKP H4 surface Fortran routines and test program,
  • the Fortran routines h4bmkp.f (0.21 Mb) for the BMKP H4 surface,
  • and the Fortran test program h4bmkp_test.f (24 kb) to check that the surface is being evaluated correctly on your computer.
  • Alternatively, the gzip'd tar-file h4prog.tar.gz (56 kb; expands to 0.23 Mb) contains all three of the above files.
• H4 ab initio data:
  • the text file h4ptsREADME.txt (18 kb) describing the two available archives of H4 energies,
  • the gzip'd tar-file cih4usen.tar.gz (3 Mb; expands to 8 Mb) containing all the energies used to fit the BMKP H4 surface. Contains 5 files of ground-state ab initio energies, 5 files of non-ab-initio energies that were generated to constrain the surface at short and long range, and the README file above that describes the contents of this archive.
  • the gzip'd tar-file cih4ean.tar.gz (17 Mb; expands to 76 Mb) containing all the ab initio H4 energies computed by the above authors. Contains 7 files of ab initio energies, including excited state energies, plus the README file above that describes the contents of this archive.
• The above data include and supersede the old H4 ab initio data published by A. I. Boothroyd, J. E. Dove, W. J. Keogh, P. G. Martin, and M. R. Peterson 1991, "Acurate Ab Initio Potential Energy Computations for the H4 System: Tests of Some Analytic Potential Energy Surfaces", J.Chem.Phys, 95, 4331-4342, and AIP document PAPS JCPSA-95-4331-170. NOTE that nine erroneous ab initio energies in this old dataset are corrected in the above new data, and the other old ab initio energies have been very slightly modified (by amounts comparable to or smaller than the quoted uncertainties).

  Follow this link to the H3 surface.

  Home page of P. G. Martin.