To what extent does the zintl-klemm formalism work? The Eu(Zn 1 - X Ge X ) 2 series
(2009) In Inorganic Chemistry 48(14). p.6380-6390- Abstract
The series of ternary polar intermetalllcs Eu(Zn
1-x
Ge
x
)
2
0≤x≤ 1) has been investigated and characterized by powder and single-crystal X-ray diffraction as well as physical property measurements. For 0.50(2) <x< 0.75(2), this series shows a homogeneity width of hexagonal AIB
2
-type phases (space group P6/mmm, Pearson symbol hP3) with Zn and Ge atoms statistically distributed In the planar... (More)
(Less)
The series of ternary polar intermetalllcs Eu(Zn
1-x
Ge
x
)
2
0≤x≤ 1) has been investigated and characterized by powder and single-crystal X-ray diffraction as well as physical property measurements. For 0.50(2) <x< 0.75(2), this series shows a homogeneity width of hexagonal AIB
2
-type phases (space group P6/mmm, Pearson symbol hP3) with Zn and Ge atoms statistically distributed In the planar polyanionlc 6
3
nets. As the Ge content increases In this range, a decreases from 4.3631(6) Å to 4.2358(6) Å, while c Increases from 4.3014(9) Å to 4.5759(9) Å, resulting In an increasing da ratio. Furthermore, the Zn-Ge bond distance in the hexagonal net drops from 2.5190(3) Å to 2.4455(3) Å, while the anisotropy of the displacement ellipsoids significantly increases along the c direction. For x < 0.50 and x > 0.75, respectively, orthorhombic KHg
2
-type and trigonal EuGe
2
-type phases occur as a second phase in mixtures with an AIB
2
-type phase. Diffraction of the x= 0.75(2) sample shows Incommensurate modulation along the c direction; a structural model In super space group P31 (00y)00s reveals puckered 6
3
nets. Temperature-dependent magnetic susceptibility measurements for two AIB
2
-type compounds show Curie-Weiss behavior above 40.0(2) K and 45.5(2) K with magnetic moments of 7.98(1 ) μB for Eu(Zn
0.48
Ge
0.52(2)
)
2
and 7.96(1 ) μB for Eu(Zn
0.30
Ge
0.70(2)
)
2
, respectively, Indicating a (4f)
7
electronic configuration for Eu atoms (Eu
2+
). The Zintl- Klemm formalism accounts for the lower limit of Ge content in the AIB
2
-type phases but does not identify the observed upper limit. In a companion paper, the intrinsic relationships among chemical structures, compositions, and electronic structures are analyzed by electronic structure calculations.
- author
- You, Tae Soo ; Lidin, Sven LU ; Gourdon, Olivier ; Wu, Yaqiao and Miller, Gordon J.
- publishing date
- 2009-07-20
- type
- Contribution to journal
- publication status
- published
- in
- Inorganic Chemistry
- volume
- 48
- issue
- 14
- pages
- 11 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:67650462878
- ISSN
- 0020-1669
- DOI
- 10.1021/ic900628k
- language
- English
- LU publication?
- no
- id
- f5b4ac90-8776-4656-9848-abc477f73923
- date added to LUP
- 2019-04-08 15:03:24
- date last changed
- 2022-02-15 17:53:48
@article{f5b4ac90-8776-4656-9848-abc477f73923,
abstract = {{<p><br>
The series of ternary polar intermetalllcs Eu(Zn <br>
<sub>1-x</sub><br>
Ge <br>
<sub>x</sub><br>
) <br>
<sub>2</sub><br>
0≤x≤ 1) has been investigated and characterized by powder and single-crystal X-ray diffraction as well as physical property measurements. For 0.50(2) <x< 0.75(2), this series shows a homogeneity width of hexagonal AIB <br>
<sub>2</sub><br>
-type phases (space group P6/mmm, Pearson symbol hP3) with Zn and Ge atoms statistically distributed In the planar polyanionlc 6 <br>
<sup>3</sup><br>
nets. As the Ge content increases In this range, a decreases from 4.3631(6) Å to 4.2358(6) Å, while c Increases from 4.3014(9) Å to 4.5759(9) Å, resulting In an increasing da ratio. Furthermore, the Zn-Ge bond distance in the hexagonal net drops from 2.5190(3) Å to 2.4455(3) Å, while the anisotropy of the displacement ellipsoids significantly increases along the c direction. For x < 0.50 and x > 0.75, respectively, orthorhombic KHg <br>
<sub>2</sub><br>
-type and trigonal EuGe <br>
<sub>2</sub><br>
-type phases occur as a second phase in mixtures with an AIB <br>
<sub>2</sub><br>
-type phase. Diffraction of the x= 0.75(2) sample shows Incommensurate modulation along the c direction; a structural model In super space group P31 (00y)00s reveals puckered 6 <br>
<sup>3</sup><br>
nets. Temperature-dependent magnetic susceptibility measurements for two AIB <br>
<sub>2</sub><br>
-type compounds show Curie-Weiss behavior above 40.0(2) K and 45.5(2) K with magnetic moments of 7.98(1 ) μB for Eu(Zn <br>
<sub>0.48</sub><br>
Ge <br>
<sub>0.52(2)</sub><br>
) <br>
<sub>2</sub><br>
and 7.96(1 ) μB for Eu(Zn <br>
<sub>0.30</sub><br>
Ge <br>
<sub>0.70(2)</sub><br>
) <br>
<sub>2</sub><br>
, respectively, Indicating a (4f) <br>
<sup>7</sup><br>
electronic configuration for Eu atoms (Eu <br>
<sup>2+</sup><br>
). The Zintl- Klemm formalism accounts for the lower limit of Ge content in the AIB <br>
<sub>2</sub><br>
-type phases but does not identify the observed upper limit. In a companion paper, the intrinsic relationships among chemical structures, compositions, and electronic structures are analyzed by electronic structure calculations.</p>}},
author = {{You, Tae Soo and Lidin, Sven and Gourdon, Olivier and Wu, Yaqiao and Miller, Gordon J.}},
issn = {{0020-1669}},
language = {{eng}},
month = {{07}},
number = {{14}},
pages = {{6380--6390}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Inorganic Chemistry}},
title = {{To what extent does the zintl-klemm formalism work? The Eu(Zn
<sub>1</sub>
-
<sub>X</sub>
Ge
<sub>X</sub>
)
<sub>2</sub>
series}},
url = {{http://dx.doi.org/10.1021/ic900628k}},
doi = {{10.1021/ic900628k}},
volume = {{48}},
year = {{2009}},
}