It is not appropriate to summarize or conclude this volume on the basic theory and methods of electronic structure. The field is evolving rapidly with new advances in basic theory, algorithms, and computational methods. New developments and applications are opening unforeseen vistas. Volumes of information are now available on-line at thousands of sites.

It is more appropriate to provide a resource for information that will be updated in the future, on-line information available at a site maintained at the University of Illinois:

http://ElectronicStructure.org

A link is maintained at the Cambridge University Press site:

http://books.cambridge.org/0521782856.htm

Resources for materials computation are maintained by the Materials Computation Center at the University of Illinois, supported by the National Science Foundation:

http://www.mcc.uiuc.edu/

Additional sites include the Department of Physics, the electronic structure group at the University of Illinois, and the author's home page:

http://www.physics.uiuc.edu/

http://www.physics.uiuc.edu/research/ElectronicStructure/

http://w3.physics.uiuc.edu/~rmartin/homepage/

The on-line information includes:

• Additional material coordinated with descriptions in this book, as well as future updates, corrections, additions, and convenient feedback forms.

• Information related to many-body methods beyond the scope of this volume.

• Links to courses, tutorials, and codes maintained at the University of Illinois. Specific codes are meant for pedagogical use, teaching, or individual study, and are coordinated with descriptions in this book, for example, the general purpose empirical pseudopotential and tight-binding code (TBPW) in App. N.

• Links to codes for electronic structure calculations. This will include resources at the Materials Computation Center and many other sites.

• […]