Structure of two-dimensional hard-disk mixtures: Modified fundamental-measure theory

A modified fundamental-measure theory (MFMT), which is based on the semiempirical equation of state for the hard-disk mixtures, has been employed for studying the uniform and nonuniform structural properties of hard-disk mixtures. The test-particle method has been used to calculate the radial distribution functions of hard-disk mixtures. The particle density distributions near the large hard disk and within the hard circular cavity have been studied, and molecular dynamics simulations have been carried out to compare with the MFMT and other approximations. The depletion interactions acting between two large hard disks in a bath of the smaller hard disks and disk–disk second virial coefficients B2B2 due to the disk-mediated interactions have been studied. Comparison with computer simulations shows that the MFMT yields an excellent agreement with computer simulation data even for higher packing fractions. The MFMT can provide an accurate reference for the further development of the statistical–thermodynamic theory of complex fluids at uniform and nonuniform conditions.