Viladot, DésiréePortillo i Serra, JoaquimGemí, MauroNicolopoulos, StavrosLlorca i Isern, Núria2014-05-232015-12-3120141431-9276https://hdl.handle.net/2445/54505The structure determination of an HfSi4 precipitate has been carried out by a combination of two precession electron diffraction techniques: high precession angle, 2.2°, single pattern collection at eight different zone axes and low precession angle, 0.5°, serial collection of patterns obtained by increasing tilts of 1°. A three-dimensional reconstruction of the associated reciprocal space shows an orthorhombic unit cell with parameters a = 11.4 Å, b = 11.8 Å, c = 14.6 Å, and an extinction condition of (hkl) h + k odd. The merged intensities from the high angle precession patterns have been symmetry tested for possible space groups (SG) fulfilling this condition and a best symmetrization residual found at 18% for SG 65 Cmmm. Use of the SIR2011 direct methods program allowed solving the structure with a structure residual of 18%. The precipitate objects of this study were reproducibly found in a newly implemented alloy, designed according to molecular orbital theory.8 p.application/pdfeng(c) Cambridge University Press, 2014Microscòpia electrònica de transmissióEstructura cristal·lina (Sòlids)TomografiaNanotecnologiaTransmission electron microscopyLayer structure (Solids)TomographyNanotechnologyinfo:eu-repo/semantics/article6294392014-05-22info:eu-repo/semantics/openAccess