Abstract by Christopher Yost

Personal Infomation

Presenter's Name

Christopher Yost



Degree Level




Abstract Infomation


Physics and Astronomy

Faculty Advisor

Branton Campbell


Algebraic search for cooperative-rotational rigid-unit modes


Crystalline solids consisting of three-dimensional networks of interconnected polyhedra or other rigid units are ubiquitous amongst functional materials.  In many cases, application-critical properties are sensitive to the rotations of individual rigid units.  But the shared atoms that connect the rigid units together impose severe constraints on any rotational degrees of freedom, which must then be cooperative throughout the entire network.  A purely algebraic approach to RUM identification has been developed, wherein the constraints of interconnectedness are applied to a linear system of equations.  The effectiveness of this approach in cases where the RUMs are imperfect (distorted the rigid bodies slightly) but nearly provide solutions, depends on the details of the algorithm used to solve the system of equations.  We’ll explain some of the issues involved. Additionally, we will discuss how the approach has been integrated into a software that will be available to the public through an online tool that can perform the entire process in minutes.