Pratim Kumar Chattaraj & Swapan Kumar Ghosh 
Concepts and Methods in Modern Theoretical Chemistry, Two Volume Set [PDF ebook] 

Offering chapters written by experts in their fields, this two-volume set covers the major areas of research in theoretical chemistry. The books enable readers to learn how concepts from ab initio quantum chemistry, density functional theory (DFT), and molecular simulation can be used to describe, understand, and predict electronic structure, chemical reactivity, and dynamics. The first book focuses on the electronic structure and reactivity of many-electron systems, and the second book deals with the statistical mechanical treatment of collections of such systems.