Theoretical Chemistry: Advances and Perspectives, Volume 2 covers all aspects of theoretical chemistry. This book reviews the techniques that have been proven successful in the study of interatomic potentials in order to describe the interactions between complex molecules. The ground state properties of the interacting electron gas when a magnetic field is present are also elaborated, followed by a discussion on the Gellman-Brueckner-Macke theory of the correlation energy that has applications in atomic and molecular systems. This volume considers the instability of the Hartree-Fock ground state in a magnetic field and very high magnetic fields that are pertinent to the structure of matter in collapsed stellar objects. The electron-hole plasma in certain highly-doped semiconductors and many-electron correlation problem are likewise included. This publication is a good reference for students and researchers conducting work on the mathematical description of chemistry.