> In TiO2 host the Nd dopant is 3+ , as it has been determined. The > TiO2:Nd unit cell will not be neutral, and can be considered as a > dipole. My question is how to deal with the interaction of dipoles in > WIEN2k. Check the UG for 'charged cell'. Stefaan Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm