Incommensurately modulated Nowotny chimney-ladder phases : Cr1-xMoxGe∼1.75 with x = 0.65 and 0.84
(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.
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- author
- Rohrer, F. E. ; Lind, H. ; Eriksson, L. ; Larsson, A. K. and Lidin, S. LU
- publishing date
- 2001-01-01
- 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}}, }