title: X-ray Diffraction and Rietveld Refinement in Deferrified Clays for Forensic Science.
abstract: Soil vestiges might provide information about a crime scene. The Rietveld method with X-ray diffraction data (RM-XRD) is a nondestructive technique that makes it possible to characterize minerals present in the soils. Soil clays from the metropolitan region of Curitiba (Brazil) were submitted to DCB treatment and analyzed using XRD with CuKαradiation in the step-scan mode (0.02° 2θ/5 s). The GSAS+EXPGUI software was used for RM refinement. The RM-XRD results, together with the principal component analysis (PCA) (52.6% total variance), showed the kaolinite predominance in most analyzed samples and the highest quartz contents in "site 1." Higher anatase, and gibbsite and muscovite contents influenced discrimination, mainly in "site 3" and "site 1," respectively. These results were enough to discriminate clays of four sites and two horizons using a reduced amount of sample showing that the technique can be applied to the investigation into soil vestiges.
authors.affiliation: Soil Science Department, Federal University of Paraná, Rua dos Funcionários 1540, 80035-050, Curitiba (PR), Brazil.
authors.forename: Luis V
authors.identifier: http://orcid.org/0000-0002-5807-8738
authors.initials: LV
authors.lastname: Prandel
authors.affiliation: Soil Science Department, Federal University of Paraná, Rua dos Funcionários 1540, 80035-050, Curitiba (PR), Brazil.
authors.forename: Vander de F
authors.initials: VF
authors.lastname: Melo
authors.affiliation: Soil Physics and Environmental Sciences, Department of Physics, State University of Ponta Grossa, Av. Carlos Cavalcanti 4748, 84030-900, Ponta Grossa (PR), Brazil.
authors.forename: André M
authors.initials: AM
authors.lastname: Brinatti
authors.affiliation: Soil Physics and Environmental Sciences, Department of Physics, State University of Ponta Grossa, Av. Carlos Cavalcanti 4748, 84030-900, Ponta Grossa (PR), Brazil.
authors.forename: Sérgio da C
authors.initials: SDC
authors.lastname: Saab
authors.affiliation: Technical and Scientific Sector, Federal Police Department, Rua Professora Sandália Monzon 210, 82640-040, Curitiba (PR), Brazil.
authors.forename: Fábio A S
authors.initials: FAS
authors.lastname: Salvador
keywords: crystallite size; dithionite-citrate-bicarbonate; forensic science; gibbsite; kaolinite; multivariate analysis; rietveld method