Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Incommensurately modulated Nowotny chimney-ladder phases : Cr1-xMoxGe∼1.75 with x = 0.65 and 0.84

Rohrer, F. E. ; Lind, H. ; Eriksson, L. ; Larsson, A. K. and Lidin, S. LU (2001) In Zeitschrift fur Kristallographie 216(4). p.190-198
Abstract

The crystal structures of two new ternary, incommensurately modulated phases in the Cr/Mo/Ge system, Cr1-xMoxGe∼1.75 with x = 0.65 and 0.84, have been refined using the same composite approach as for the earlier reported compounds, (Mo/Rh)11Ge18 and (Mo/Rh)13Ge22, from the Mo/Rh/Ge system. The composite model consists of a rather stable diamond-like transition metal substructure and a helical main group element arrangement. The same super space group pair, W: P4/nnc: ql̄q1 P: I41/amd: 11̄ss, the same positions and modulation waves were used. The refinements of the new phases in the Cr/Mo/Ge system converged rapidly to R-values below 5% with GOF of... (More)

The crystal structures of two new ternary, incommensurately modulated phases in the Cr/Mo/Ge system, Cr1-xMoxGe∼1.75 with x = 0.65 and 0.84, have been refined using the same composite approach as for the earlier reported compounds, (Mo/Rh)11Ge18 and (Mo/Rh)13Ge22, from the Mo/Rh/Ge system. The composite model consists of a rather stable diamond-like transition metal substructure and a helical main group element arrangement. The same super space group pair, W: P4/nnc: ql̄q1 P: I41/amd: 11̄ss, the same positions and modulation waves were used. The refinements of the new phases in the Cr/Mo/Ge system converged rapidly to R-values below 5% with GOF of 2.53 and 3.71, respectively. Each structure is built by two sub lattices with the parameters - a, cx and the modulation vector qx - for Ge and a, cT and qT for the transition metals. The refined data for x = 0.65 are found to be a = 5.935(2), cx = 2.770(1), cT = 4.839(1), qx = 0.428 [001]*, qT = 0.253 [001]* and for x = 0.84, a = 5.963(1), cx = 2.786(1), cT = 4.875(1), qx = 0.430 [001]*, qT = 0.264 [001]*. It is clearly shown the composite approach is applicable to different chimney-ladder compounds, even though they have quite different compositions and hence q-vectors.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; and
publishing date
type
Contribution to journal
publication status
published
in
Zeitschrift fur Kristallographie
volume
216
issue
4
pages
9 pages
publisher
Oldenbourg Verlag
external identifiers
  • scopus:0035053564
ISSN
0044-2968
DOI
10.1524/zkri.216.4.190.23255
language
English
LU publication?
no
id
58f9186c-3c3a-48b3-a083-08688b697afc
date added to LUP
2019-04-08 15:57:31
date last changed
2022-04-25 22:45:55
@article{58f9186c-3c3a-48b3-a083-08688b697afc,
  abstract     = {{<p>The crystal structures of two new ternary, incommensurately modulated phases in the Cr/Mo/Ge system, Cr<sub>1-x</sub>Mo<sub>x</sub>Ge<sub>∼1.75</sub> with x = 0.65 and 0.84, have been refined using the same composite approach as for the earlier reported compounds, (Mo/Rh)<sub>11</sub>Ge<sub>18</sub> and (Mo/Rh)<sub>13</sub>Ge<sub>22</sub>, from the Mo/Rh/Ge system. The composite model consists of a rather stable diamond-like transition metal substructure and a helical main group element arrangement. The same super space group pair, W: P4/nnc: ql̄q1 P: I4<sub>1</sub>/amd: 11̄ss, the same positions and modulation waves were used. The refinements of the new phases in the Cr/Mo/Ge system converged rapidly to R-values below 5% with GOF of 2.53 and 3.71, respectively. Each structure is built by two sub lattices with the parameters - a, c<sub>x</sub> and the modulation vector q<sub>x</sub> - for Ge and a, c<sub>T</sub> and q<sub>T</sub> for the transition metals. The refined data for x = 0.65 are found to be a = 5.935(2), c<sub>x</sub> = 2.770(1), c<sub>T</sub> = 4.839(1), q<sub>x</sub> = 0.428 [001]*, qT = 0.253 [001]* and for x = 0.84, a = 5.963(1), c<sub>x</sub> = 2.786(1), c<sub>T</sub> = 4.875(1), q<sub>x</sub> = 0.430 [001]*, q<sub>T</sub> = 0.264 [001]*. It is clearly shown the composite approach is applicable to different chimney-ladder compounds, even though they have quite different compositions and hence q-vectors.</p>}},
  author       = {{Rohrer, F. E. and Lind, H. and Eriksson, L. and Larsson, A. K. and Lidin, S.}},
  issn         = {{0044-2968}},
  language     = {{eng}},
  month        = {{01}},
  number       = {{4}},
  pages        = {{190--198}},
  publisher    = {{Oldenbourg Verlag}},
  series       = {{Zeitschrift fur Kristallographie}},
  title        = {{Incommensurately modulated Nowotny chimney-ladder phases : Cr<sub>1-x</sub>Mo<sub>x</sub>Ge<sub>∼1.75</sub> with x = 0.65 and 0.84}},
  url          = {{http://dx.doi.org/10.1524/zkri.216.4.190.23255}},
  doi          = {{10.1524/zkri.216.4.190.23255}},
  volume       = {{216}},
  year         = {{2001}},
}