Using Material Properties in Desgn Tables

I am looking to use formulea in the design table that is a function of feature size (dimensions) and a material property (In this case Thermal Conductivity) to drive a custom property which will give me use full information later in my design process.

What is the necessary syntax to call up a given property such as Thermal Conductivity of the material assigned to the part.

Thanks for your help

Stuart

SolidworksConfigurations design Tables