Structure factor of model bidisperse ferrofluids with relatively weak interparticle interactions

Author(s)
Ekaterina Novak, Elena Minina, Elena Pyanzina, Sofia Kantorovich, Alexey Ivanov
Abstract

In the present manuscript we develop a theoretical approach to describe the pair correlation function of bidisperse magnetic dipolar hard- and soft-spheres. We choose bidisperse system as the first step to allow for polydispersity when studying thermodynamics of magnetic fluids. Using diagram technique we calculate the virial expansion of the pair correlation function up to the first order in density and fourth order in the dipolar strength. Even though, the radial distribution functions are extremely sensitive to the steric potential, we show that the behaviour of the isotropic centre-centre structure factor is almost indifferent to the type of the short-range repulsion. We extensively compare our theoretical results to the data of molecular dynamics simulations, which helps us to understand the range of validity of the virial expansion both on density and magnetic dipolar strength. We also investigate the influence of the granulometric composition on the height, width, and position of the structure factor first peak in order to clarify whether it is possible to extract structural information from experimentally measured small angle neutron scattering intensities.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Ural Federal University, Universität Stuttgart
Journal
Journal of Chemical Physics
Volume
139
No. of pages
14
ISSN
0021-9606
DOI
https://doi.org/10.1063/1.4834635
Publication date
12-2013
Peer reviewed
Yes
Austrian Fields of Science 2012
103023 Polymer physics, 103017 Magnetism, 103029 Statistical physics
Keywords
Portal url
https://ucrisportal.univie.ac.at/en/publications/761dcf6f-3610-4631-8224-52f3aec3f23e