| Institution: | (1) Department of Earth Sciences, University of Cambridge, UK;(2) Department of Chemistry, Imperial College, London, UK;(3) Department of Physics, University of Illinois, Urbana IL, 61801, USA;(4) Institut de Ciencia de Materials de Barcelona, – CSIC, 08193 Bellaterra, Spain;(5) Department of Physics, Lyman Laboratory, Harvard University, Cambridge, MA 02138, USA;(6) Departamento de Fisica de la Materia Condensada and, Instituto Nicolas Cabrera, Universidad Autonoma, 28049 Madrid, Spain |
| Abstract: | The use of quantum mechanics methods within the formalism of density functional theory requires a method to represent the electron wave functions. We compare the use of strictly localized basis functions based on atomic orbitals with the use of plane waves for the study of mineral properties and behaviour. Strictly localized functions enable the computational resources to scale linearly with the size of the system, whereas plane-wave methods scale more as the cube power of the system size, and for this reason the use of localized functions will be preferred for studies of large sizes. We present test results obtained from studies of cation ordering in spinel, garnet and amphibole phases, the high-pressure displacive phase transition in cristobalite, and the intercalation of organic molecules into pyrophyllite. We conclude that the use of localized basis sets provides a useful route forward for quantum mechanical studies of large-scale mineral problems.Received: 5 July 2001 |
