Electronic molecules in solids

Department of Physics, School of Physics and Mathematical Sciences Loughborough University - LE11 3TU, UK

Received: 4 January 2001
Accepted: 5 April 2001

Abstract

We show that at certain conditions electronic molecules may arise in solids with narrow bands. The behaviour of the electronic molecules is very quantum, their shapes and sizes are not well defined while varying in some limits. In many situations, for example in metal and magnetic oxides, due to the strong Coulomb screening they may have primarily stringed linear form and therefore we have named them electron strings. In general, the form of electronic molecules may be arbitrary and particularly is determined by the structure of an effective electron-electron interaction at short and long distances. We estimate the size and the shape of the electron molecules which may arise in oxide materials. In oxides like cuprates, nickelates and manganites these electron molecules —in particular, electron strings, may be responsible for the creation of the stripe phases.