title: Direct reconstruction of the two-dimensional pair distribution function in partially ordered systems with angular correlations.
abstract: An x-ray scattering approach to determine the two-dimensional (2D) pair distribution function (PDF) in partially ordered 2D systems is proposed. We derive relations between the structure factor and PDF that enable quantitative studies of positional and bond-orientational (BO) order in real space. We apply this approach in the x-ray study of a liquid crystal (LC) film undergoing the smectic-A-hexatic-B phase transition, to analyze the interplay between the positional and BO order during the temperature evolution of the LC film. We analyze the positional correlation length in different directions in real space.
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607 Hamburg, Germany.|National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe shosse 31, Moscow 115409, Russia.
authors.forename: I A
authors.initials: IA
authors.lastname: Zaluzhnyy
authors.affiliation: European XFEL GmbH, Holzkoppel 4, D-22869 Schenefeld, Germany.
authors.forename: R P
authors.initials: RP
authors.lastname: Kurta
authors.affiliation: National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe shosse 31, Moscow 115409, Russia.
authors.forename: A P
authors.initials: AP
authors.lastname: Menushenkov
authors.affiliation: FSRC "Crystallography and Photonics," Russian Academy of Sciences, Leninskii prospect 59, 119333 Moscow, Russia.|Landau Institute for Theoretical Physics, Russian Academy of Sciences, prospect akademika Semenova 1-A, Chernogolovka 142432, Russia.
authors.forename: B I
authors.initials: BI
authors.lastname: Ostrovskii
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607 Hamburg, Germany.|National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe shosse 31, Moscow 115409, Russia.
authors.forename: I A
authors.initials: IA
authors.lastname: Vartanyants