A detailed investigation of the structure and magnetic properties of Tm2Fe17−xGax(x=0, 1, 2, 3, 4, 5, 6, 7, and 8) compounds has been performed by means of x-ray-diffraction, neutron-diffraction, magnetization, and ac-susceptibility measurements. Crystal-structure studies have shown that the prepared samples are single phase with the hexagonal Th2Ni17 for x⩽3 and the rhombohedral Th2Zn17 structure for x⩾5. In Tm2Fe13Ga4 the Th2Zn17 structure coexists with the Th2Ni17 structure. Substitution of Ga for Fe in Tm2Fe17 leads to an increase of the unit-cell volume, which is linear with the Ga concentration. In Tm2Fe17−xGax, the saturation magnetization at 1.5 K decreases linearly with increasing Ga content with a rate of 2.3 μB per substituted Ga atom. The Curie temperature is found first to increase with increasing Ga content, going through a maximum value of 485 K at about x=3, then to decrease. Between x=6 and 7, a minimum value of TC is reached and for higher x values TC increases again. X-ray-diffraction measurements on magnetically aligned Tm2Fe17−xGax powders show that the compounds with x⩽6 have an easy-plane type of magnetic anisotropy, whereas the compounds with x⩾7 exhibit easy c-axis anisotropy at room temperature. All Tm2Fe17−xGax compounds exhibit a spin-reorientation transition at low temperature, except for the sample with x=6, which shows an easy-magnetization direction perpendicular to the c axis in the temperature range from 5 to 300 K. For x⩽5, the spin-reorientation temperature is found first to increase with x and then to decrease, having a maximum value of 211 K at about x=3. In the samples with x⩾7, an easy-plane anisotropy was observed at low temperature, but an easy-axis preference of the magnetization at room temperature was observed. The results obtained for Tm2Fe17−xGax indicate that the mutually competing Tm- and Fe-sublattice anisotropies both change their sign with increasing Ga concentration.

1.
J. M. D.
Coey
and
H.
Sun
,
J. Magn. Magn. Mater.
87
,
L251
(
1990
).
2.
X. P.
Zhong
,
R. J.
Radwanski
,
F. R.
de Boer
,
T. H.
Jacobs
, and
K. H. J.
Buschow
,
J. Magn. Magn. Mater.
86
,
333
(
1990
).
3.
K. S. V. L.
Narasimhm
and
W. E.
Wallace
, in
Magnetism and Magnetic Materials
, edited by
C. D.
Graham
and
J. J.
Rhyne
,
AIP Conf. Proc.
No. 18 (
AIP
,
New York
,
1974
), p.
1248
.
4.
D.
McNeely
and
H.
Oesterreicher
,
J. Less-Common Met.
44
,
183
(
1976
).
5.
F.
Weitzer
,
K.
Hiebl
, and
P.
Rogl
,
J. Appl. Phys.
65
,
4963
(
1989
).
6.
T. H.
Jacobs
,
K. H. J.
Buschow
,
G. F.
Zhou
,
X.
Li
, and
F. R.
de Boer
,
J. Magn. Magn. Mater.
116
,
220
(
1992
).
7.
T. H.
Jacobs
,
K. H. J.
Buschow
,
G. F.
Zhou
, and
F. R.
de Boer
,
Physica B
179
,
177
(
1992
).
8.
B. G.
Shen
,
F. W.
Wang
,
L. S.
Kong
, and
L.
Cao
,
J. Phys.: Condens. Matter
5
,
L685
(
1993
).
9.
Z.
Wang
and
R. A.
Dunlap
,
J. Phys.: Condens. Matter
5
,
2407
(
1993
).
10.
R. A.
Dunlap
,
Z.
Wang
, and
M.
Foldeaki
,
J. Appl. Phys.
76
,
6737
(
1994
).
11.
J. L.
Wang
,
R. W.
Zhao
,
N.
Tang
,
W. Z.
Li
,
Y. H.
Gao
,
F. M.
Yang
, and
F. R.
de Boer
,
J. Appl. Phys.
76
,
6740
(
1994
).
12.
G. J.
Long
,
G. K.
Marasinghe
,
S.
Mishra
,
O. A.
Pringle
,
Z.
Hu
,
W. B.
Yelon
,
D. P.
Middleton
,
K. H. J.
Buschow
, and
F.
Grandjean
,
J. Appl. Phys.
76
,
5383
(
1994
).
13.
Z.
Hu
,
W. B.
Yelon
,
S.
Mishra
,
G. J.
Long
,
O. A.
Pringle
,
D. P.
Middleton
,
K. H. J.
Buschow
, and
F.
Grandjean
,
J. Appl. Phys.
76
,
443
(
1994
).
14.
B. G.
Shen
,
Z. H.
Cheng
,
B.
Liang
,
H. Q.
Guo
,
J. X.
Zhang
,
H. Y.
Gong
,
F. W.
Wang
,
Q. W.
Yan
, and
W. S.
Zhan
,
Appl. Phys. Lett.
67
,
1621
(
1995
).
15.
B. G.
Shen
,
Z. H.
Cheng
,
H. Y.
Gong
,
B.
Liang
,
Q. W.
Yan
,
F. W.
Wang
,
J. X.
Zhang
,
S. Y.
Zhang
, and
H. Q.
Guo
,
J. Alloys Compd.
226
,
51
(
1995
).
16.
Z. H.
Cheng
,
B. G.
Shen
,
B.
Liang
,
J. X.
Zhang
,
F. W.
Wang
,
S. Y.
Zhang
,
J. G.
Zhao
, and
W. S.
Zhan
,
J. Appl. Phys.
77
,
1385
(
1995
).
17.
S. R.
Mishra
,
G. J.
Long
,
O. A.
Pringle
,
D. P.
Middleton
,
Z.
Hu
,
W. B.
Yelon
,
F.
Grandjean
, and
K. H. J.
Buschow
,
J. Appl. Phys.
79
,
3145
(
1996
).
18.
H.
Luo
,
Z.
Hu
,
W. B.
Yelon
,
S.
Mishra
,
G. J.
Long
,
O. A.
Pringle
,
D. P.
Middleton
, and
K. H. J.
Buschow
,
J. Appl. Phys.
79
,
6318
(
1996
).
19.
E. E.
Alp
,
A. M.
Umarji
,
S. K.
Malik
,
G. K.
Shenoy
,
M. Q.
Huang
,
E. B.
Boltich
, and
W. E.
Wallace
,
J. Magn. Magn. Mater.
68
,
305
(
1987
).
20.
P. C. M.
Gubbens
,
A. M.
van der Kraan
,
T. H.
Jacobs
, and
K. H. J.
Buschow
,
J. Less-Common Met.
159
,
173
(
1990
).
21.
G. J.
Long
,
G. K.
Marasinghe
,
S.
Mishra
,
O. A.
Pringle
,
F.
Grandjean
,
K. H. J.
Buschow
,
D. P.
Middleton
,
W. B.
Yelon
,
F.
Pourarian
, and
O.
Isnard
,
Solid State Commun.
88
,
761
(
1993
).
22.
D. P.
Middleton
and
K. H. J.
Buschow
,
J. Alloys Compd.
206
,
L1
(
1994
).
23.
B. G.
Shen
,
H. Y.
Gong
,
B.
Liang
,
Z. H.
Cheng
, and
J. X.
Zhang
,
J. Alloys Compd.
229
,
257
(
1995
).
24.
Z. W.
Li
,
X. Z.
Zhou
, and
A. H.
Morrish
,
Phys. Rev. B
51
,
2891
(
1995
).
25.
B. G.
Shen
,
B.
Liang
,
F. W.
Wang
,
Z. H.
Cheng
,
H. Y.
Gong
,
S. Y.
Zhang
, and
J. X.
Zhang
,
J. Appl. Phys.
77
,
2637
(
1995
).
26.
H. S.
Li
,
R. C.
Mohanty
,
A.
Raman
,
C. G.
Grenier
, and
R. E.
Ferrell
,
J. Magn. Magn. Mater.
166
,
365
(
1997
).
27.
Z. H.
Cheng
,
B. G.
Shen
,
B.
Liang
,
J. X.
Zhang
,
F. W.
Wang
,
S. Y.
Zhang
, and
H. Y.
Gong
,
J. Phys.: Condens. Matter
7
,
4707
(
1995
).
28.
S.
Ridwan
,
H.
Mujamilah
,
M.
Gunawan
,
P.
Marsongkohadi
,
Q. W.
Yan
,
P. L.
Zhang
,
X. D.
Shen
,
Z. H.
Cheng
,
N.
Minakawa
, and
Y.
Hamaguchi
,
J. Phys. Soc. Jpn.
65
,
348
(
1996
).
29.
B. G.
Shen
,
Z. H.
Cheng
,
H. Y.
Gong
,
B.
Liang
,
Q. W.
Yan
, and
W. S.
Zhan
,
Solid State Commun.
95
,
813
(
1995
).
30.
F.
Izumi
,
Kobutsugaku Zasshi
17
,
37
(
1985
).
31.
Z. W.
Li
and
A. H.
Morrish
,
J. Phys.: Condens. Matter
7
,
6727
(
1995
).
32.
H. R.
Kirchmayr
and
C. A.
Poldy
,
J. Magn. Magn. Mater.
8
,
1
(
1978
).
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