Electronic, Magnetic, and Thermodynamic Properties of Molecular Solids

Florida State University, Tallahassee FL

Investigators

Abstract

This individual investigator award provides support for an investigation of the electronic and magnetic ground states of molecular solids. These are a unique class of materials, where organic molecules are stacked in chain or plane-like structures. The research is motivated by recent developments involving molecular solids where superconducting and/or magnetic properties appear under special conditions of composition, temperature, magnetic fields, and electric fields. The project involves investigations of three sequential hierarchies of molecular solids where electrical charge is introduced in different ways: 1) an unusual organic material where charge is introduced by a magnetic ion; 2) a single component molecular solid, engineered to produce a metallic state solely by the molecular arrangement (without need for a counter ion); and 3) chemically engineered, or "functionalized" forms of the acenes (i.e. tetracene and pentacene). In the latter, electrical charge will be introduced at the surface of thin films or crystals optically and/or with an electric field. Both the fundamental physics, and potential new device applications for these molecular systems, will be pursued. The graduate students involved in this research will obtain training that will provide them with the skills needed for a future career in academia or in industrial or government laboratories. In addition, a strong commitment to educational outreach K-16 and teacher programs is integrated into the research agenda. Recent developments indicate that molecular solids are likely to form the basis for future technologies utilizing bio-molecular materials. Molecular solids are a unique class of materials where organic molecules are stacked in chain or plane-like structures. Here superconducting, and/or magnetic properties appear under special conditions of composition, temperature, magnetic fields, and electric fields. This individual investigator project will probe the electronic and magnetic properties of molecular solids. The project will study three kinds of molecular structures: first, where both electrical charge and magnetism is introduced into the molecular layers; second, where a molecular solid is engineered to conduct electrically, solely by the molecular arrangement; and third, where "functionalized" forms of molecular building blocks are chemically engineered. Here optical and electric field methods will be employed to switch the conducting and magnetic properties on and off. New device applications, and fundamental science, will be pursued in these molecular systems. The graduate students involved in this research will obtain training that will provide them with the skills needed for a future career in academia or in industrial or government laboratories. In addition, a strong commitment to educational outreach K-16 and teacher programs is integrated into the research agenda.