title: Structure determination of CdS and ZnS nanoparticles: direct modeling of synchrotron-radiation diffraction data.
abstract: We introduce a modified method of powder-diffraction data analysis to obtain precise structural information on freestanding ZnS and CdS nanoparticles with diameters well below 5 nm, i.e., in a range where common bulk-derived approaches fail. The method is based on the Debye equation and allows us to access the crystal structure and the size of the particles with high precision. Detailed information on strain, relaxation effects, stacking faults, and the shape of the particles becomes available. We find significant size differences between our new results and those obtained by established methods, and conclude that a mixed zinc-blende/wurtzite stacking and significant lattice distortions occur in our CdS nanoparticles. Our approach should have direct impact on the understanding and modeling of quantum size effects in nanoparticles.
authors.affiliation: Lehrstuhl für Experimentelle Physik II, Universität Würzburg, D-97074 Würzburg, Germany. kumpf@physik.uni-wuerzburg.de
authors.forename: C
authors.initials: C
authors.lastname: Kumpf
authors.forename: R B
authors.initials: RB
authors.lastname: Neder
authors.forename: F
authors.initials: F
authors.lastname: Niederdraenk
authors.forename: P
authors.initials: P
authors.lastname: Luczak
authors.forename: A
authors.initials: A
authors.lastname: Stahl
authors.forename: M
authors.initials: M
authors.lastname: Scheuermann
authors.forename: S
authors.initials: S
authors.lastname: Joshi
authors.forename: S K
authors.initials: SK
authors.lastname: Kulkarni
authors.forename: C
authors.initials: C
authors.lastname: Barglik-Chory
authors.forename: C
authors.initials: C
authors.lastname: Heske
authors.forename: E
authors.initials: E
authors.lastname: Umbach