Fig. 3. (a) Thermal conductivity of the simple cubic structure without adsorbed gas as a function of pore size (top axis) and crystal density (bottom axis). (b) Thermal conductivity of MOF crystals triangular (triangles) and hexagonal (hexagons) channels parallel (filled symbols) and perpendicular (empty symbols) to the channel directions along with simple cubic structure (filled squares) as a function of pore size. The lines in (b) are power law fits to the data points with exponents: squares: –1.78, filled hexagons: –2.13, filled triangles: –2.19, empty hexagons: –1.07 and empty triangles: –1.14.