Poole Ch.P., Jr. Handbook of Superconductivity

386

Chapter 8: Crystal Structures of High-T~ Superconducting Cuprates

Atom WP PS x y z Occ.

T1 a 4(e)

4mm

0 0 0.2799

1 1

0.3552

Ba 4(e)

4mm ~

Cu(1 ) 4(e)

4mm

0 0 0.4104

1 1

0.4537

Ca b 4(e)

4mm ~

1

Cu(2) 2(b)

4/mmm 0 0

1 1

0.2719

O(1) 4(e)

4mm ~

0(2) 4(e)

4mm

0 0 0.3412

1 0.4125

0(3) 8(g)

2mm . 0

1 1

0(4) 4(c)

mmm . 0 ~

aT1 = Tlo.85Cao.15; site may be partly vacant.

b Ca = Cao.88Tlo.12.

Compound a (A) c (A) T c (K) Ref.

T11.94Ba2Ca2.o6Cu301 o 3.8503 3 5.88 125

Hg 1.4Tlo.6B a2Ca2Cu30y a 3.840 35.69 45

a

Prepared at 5 GPa; nominal composition.

References: 1, Torardi

et al.

(1988b); 2, Tatsuki

et al.

(1996).

2223

(Bio.86Pbo. 14)2Sr2Ca2Cu3010.24

A2B2C2D301o , ti38,

(139)

I4/mmm-ge6cb

-DO2-.

C-D02-. C-DO 2-OB-A O-OA-BO-

Bil.72Pbo.28Sr2Ca2Cu301o.24, a T c -- 110 K, b PN, RT,

Rwp

= 0.0643 (Miehe

et al.,

1990)

(37)

A2aa (Ccc2),

a -- 5.4029, b = 5.4154, c = 37.074A, c Z = 4

al + a2, -al + a2, c; origin shift 0 1 1

Atom WP PS x y z

Occ.

Bi ax 8(d) 1 -0.036 0.233 0.0411

Sr e 8(d) 1 0.490 0.255 0.1148

Cu(1) 8(d) 1 0.000 0.246 0.1619

Ca ~ 8(d) 1 0.468 0.257 0.2072

1 1

Cu(2) e 4(c) 2.. 0.000 ~

O(1) e 8(d) 1 0.425 0.139 0.0434

O(2) f 8(d) 1 0.230 0.544 0.0372

0(3) 8(d) 1 0.047 0.253 0.0956

0(4) 8(d) 1 0.274 0.498 0.1637

0(5) 8(d) 1 0.252 -0.006 0.1650

0(6) 8(d) 1 0.230 0.002 0.2486

0.12

a

Composition Bil.89Pbo.31Sr2.ooCal.91Cu3.ooOlo.25 from microprobe and chemical analysis.

b Value for Bil.84Pbo.34Srl.91Ca2.o3Cu3.o6Oy (nominal composition) taken from Koyama

et al.

(1988).

c Average structure, additional reflections indicate incommensurate modulation (q ~ a*/7.2).

d Bi = Bio.86Pbo.14.

eRefined occupancies: Bi, 0.96; Sr, 0.97; Ca, 1.11; Cu(2), 1.04; and O(1), 0.98.

fExtra O site located in the BiO layers.

(continued)

H. Crystallographic Data Sets 387

Compound

a (A) b (A) c (A) T c (K) Ref.

Bi 1.72Pb0.28 Sr2Ca2Cu30 10.24

Bil.7Pbo.3Srl.7Ca2.3Cu3Oy c

B i 1.76Pb0.24 Sr2 Ca 1.6Sbo.4Cu3010

Bi2PbSrl.7Bao.3Ca2Cu3Oy e

5.4029 5.4154 37.074 a 1 l0 b 1, 2

5.4146 5.4146 37.135 110 3

5.411 5.411 37.22 d 111 4

5.390 r 5.420 r 37.18 f 109.6 5

a

Additional reflections indicate incommensurate modulation (q ~ a*/7.2).

b Value for Bil.s4Pbo.34Srl.91Ca2.o3Cu3.o6Oy (nominal composition).

c Nominal composition.

d Space group

Amaa;

additional reflections indicate incommensurate modulations (q--a*/4.97 and

a*/6.67).

eNominal composition, composition

Bil.5oPbo.52Srl.63Bao.29Ca2.o4Cu3.ooOy

from ICP analysis.

fValue taken from figure.

References: 1, Miehe

et al.

(1990); 2, Koyama

et al.

(1988); 3, Sasry and West (1994); 4, Kijima and

Gronsky (1992); 5, Kim

et al.

(1992).

Superconductivity in the T1-Ba-Ca-Cu-O system was first reported by

Sheng and Hermann (1988b). The T1-2223 compound was identified by Politis

and Luo (1988) and Parkin

et al.

(1988a), and the first structural refinement

indicated partial disorder of T1 and Ca (Torardi

et al.,

1988b). The Ca site was

also found to be partly occupied by thallium atoms (3-7 at.%) in Hervieu

et al.

(1998b), Morosin

et al.

(199 lb), and Sinclair

et al.

(1994). Vacancies on the T1

site (occupancy 0.88-0.94) were considered in Hervieu

et al.

(1988b), Morosin

et

al. (1991

b), and Ogbome

et al.

(1992a), whereas partial substitution of T1 by Cu

(14 at.%) was reported by Sinclair

et al.

(1994). The O site in the

additional

layers was

found to be displaced from the ideal position in Ogbome

et al.

(1992a) and Morosin

et

al.

(1991 b) (16(n) 0.6112 89 0.2753, occupancy 0.234), whereas both the T1 and the

O site in the

additional

layers were split in Sinclair

et al.

(1994) (T1 in

16(m) 0.0276 0.0276 0.27921 and O in 16(m) 0.5819 0.5819 0.2756, occupancy

0.215 and 0.25).

The compound with the superconducting transition temperature of 105 K

(Maeda

et al.,

1988) was identified as Bi-2223 (Zandbergen

et al.,

1988d;

Takayama-Muromachi

et al.,

1988b; Ikeda

et al.,

1988a) and can be stabilized

by Pb (Hetherington

et al.,

1988; Endo

et al.,

1988). A pseudotetragonal subcell

(a = b -- 5.41, c = 37.09 A) and an incommensurate modulation with a transla-

tion period of~ 8.7a were reported for Bil.73Pbo.35Srl.89Cal.86Cu309.91 (Ikeda

et

al.,

1988b). The orthorhombic space groups

Fmmm

(Hetherington

et al.,

1988),

Amaa

(Kijima

et al.,

1989; Carrilo-Cabrera and G6pel, 1989), and

A2aa

(Carrilo-

Cabrera and G6pel, 1989; Miehe

et al.,

1990) were used to describe the structure

of (Bi,Pb)-2223. The structural refinement in Kijima

et al.

(1989) showed that Pb

mainly substitutes for Bi, but also for Sr and Ca (A, B, and C site, respectively).

An extra O site in the

additional

BiO layers, corresponding to the excess oxygen,

was found by Miehe

et aL (1990).

388 Chapter 8:

2234

Crystal Structures of High-T~ Superconducting Cuprates

(Tlo.82)2Ba2Ca3Cu4012

A2B2C3D4012,

ti46, (139)

14/mmm-g2e 7 a

-DO2-.C-DO2-.C-DOz-.C-DO2-OB-AO-OA-BO-

Tll.64Ba2Ca3Cu4O12, T c --- 109K, PX, R e --0.1396

(Ogborne and Weller, 1992)

(139)

I4/mmm,

a = 3.84877, c = 42.0494A, Z = 2 Fig. 28

Atom WP PS x

z Occ.

T1 4(e)

4mmO 0

1

Ba 4(e)

4mm

Cu(1) 4(e)

4mm 0

1

Ca(l) 4(e)

4mm

Cu(2) 4(e)

4mm 0

1

Ca(2) 2(a)

4/mmm

O(1) 16(n) .m. 0.394

0(2) 4(e)

4mm 0

0(3) 8(g)

2mm . 0

0(4) 8(g)

2mm . 0

0.2757

1

2

0

1

2

0

1

2

1

2

0

1

2

1

2

0.82

0.3387

0.3866

0.4236

0.4636

1

2

0.2664

0.3234

0.3874

0.4626

0.25

Compound a (A) c (A) T c (K)

Ref.

Tll.64Ba2Ca3Cu4012 3.84877 42.0494

Hg 1.4Tlo.6Ba2Ca3Cu4Oy a 3.845 42.06

a

Prepared at 5 GPa; nominal composition.

References: 1, Ogbome and Weller (1992); 2, Tatsuki

et al.

(1996).

109

114

H. Crystallographic Data Sets 389

A superconducting T1-2234 compound (T c = 114 K) was first reported by

Hervieu

et al.

(1988a) for the composition T12Ba2Ca3Cu4012, and a structural

model was proposed in space group

I4/mmm

(a - 3.852, c = 42.00 A). Partial

disorder of T1 and Ca, corresponding to 40 at.% Ca on the T1 site and 10-15 at.%

T1 on the Ca sites, was reported by Ogborne and Weller (1994b). The T1 and the

O site in the

additional

layers were found to be partly vacant (occupancy 0.93-

0.94 and 0.95-1.00), and the occupancy of the latter was found to depend on the

annealing conditions. The superconducting transition temperature decreased to

106 K for the reduced compound.

3201

,,

A3B2DO 6, tP12,

(123)

P4/mmm-h2g2eda

-0 2 D-B O-O A-A .-O A-B O-

Pb2SrLaCul.8406, Tc = 33 K, PN, T - 292 K,

Rwp

= 0.0631

(Benschop

et

al.,

1994)

(53)

Pman (Pmna),

a = 5.3380, b = 5.4293,

c -- 12.6270 A, Z -- 2 Fig. 29

a 1 +a2, -a 1 q-a2, c

(Pbo.

67 C1"10.28 )3 ( S

ro.soLao.5o

)2 Cu 1 O6

Atom WP PS

z Occ.

Cu(1) 2(a)

2/m. . 0

Pb 4(h) m.. 0

Sr a 4(h) m.. 0

Cu(2) 2(c)

2/m . . 0

O(1) 4(h) m.. 0

0(2) 4(h) m.. 0

1

0(3) 4(g) . .2

0

0.5

-0.0095

1

_

2

0.043

0.5420

1

_

4

0

0.1381

0.3576

1

_

2

0.1475

0.3065

0.5

0.840

a

Sr = Sr05Lao. 5.

390

Chapter 8: Crystal Structures of High-Tc Superconducting Cuprates

A superconducting 3201 compound (T c --31 K) was first reported for

PbeSro.8Lal.eCu206+ 6 and a structural model was proposed in space group P2212

(a- 5.333, b- 5.421, c- 12.609 A) (Zandbergen

et al.,

1989). It was shown

that with increasing oxygen content another compound is formed and that a

miscibility gap exists between the reduced, superconducting compound (6 -~ 0)

and the oxidized, semiconducting compound (6 ~ 1.4) (Zandbergen

et al.,

1990a). The latter crystallizes with an orthorhombic subcell (a- 5.421,

b- 5.421, c- 12.652A) and an incommensurate modulation along [0 1 0]

with a translation period of ~ 3.8b. Extra oxygen atoms are located in the central

additional

(Cu) layer. The first structural refinement on the reduced compound

(Pb2SrLaCu206) was carried out in space group

Pman (a -

5.3119, b - 5.4140,

c-12.6292A) (Benschop

et al.,

1991). The proposed displacements of the

oxygen atoms in the PbO layers result in four Pb-O contact distances. Space

group

Pmmm

was adopted for the refinement of the average structure of oxidized

Pb2SrLaCu207.5 (a- 3.8365, b- 3.8615, c- 12.672A) and the incommensu-

rate modulation with a translation period of 3.1-3.6 was confirmed in Benschop

et al.

(1994). The structure of a (Pb,Cu)-3201 compound prepared by a

polymerized complex method, was claimed to be tetragonal for 1.7 _< 6 _< 2

(Kato

et al.,

1995).

An iodine-intercalated (Bi,I)-3201 compound, (BizI)SrzCuOy (a- 5.40,

c- 15.76 A, T c - 22 K), was reported by Xiang

et al.

(1991).

3212 (P bo. 67Cu0.33 )3 S r 2 Y 1Cu208

A3B2CD208,

tP16, (123)

P4/mmm-ih3 g2 ba

-02D--C-.O 2D-BO-OA-A.-OA-BO-

Pb2SrzYCu308, n.s., PN, RT, R 8 -- 0.0624 (Cava

et aL,

1989)

(65)

Cmmm,

a = 5.3933, b = 5.4311, c -- 15.7334,

Z - 2 Fig. 30

a 1 +a2, --a 1 +a2, C

H. Crystallographic Data Sets

391

Atom WP PS x y z Occ.

Cu(1) 2(a)

mmm 0 0 0

1 0

0.1117

Pb 4(/)

mm2

Sr 4(k)

mm2 0 0

0.2793

1 0 0.3938

Cu(2) 4(/)

mm2

1

Y 2(d)

mmm 0 0

O(1) 16(r) 1 0.051 0.074 0.1151

1 0 0.2486

O(2) 4(/)

mm2

1 1 0.4082

0(3) 8(m) . .2 ~

0.25

Compound a (/k) b (A) c (A) T~ (K) Ref.

Pb2Sr2.24Ndo.76Cu308 5.435 5.463 15.817 n.s. 1

Pb2 SrzYCu308 5.3933 5.4311 15.7334 n.s. 2

PbzSrzYCu309.47 3.838 3.870 15.845 a n.s. 3, 4

PbzSrzYo.73Cao.27Cu307.8

5.3835 5.4091 15.784 b 67 5

a

Space group

Pmmm;

additional reflections indicate superstructure (4a, 2b, c).

b Space group

Pman.

References: 1, Cava

et al.

(1988); 2, Cava

et al.

(1989); 3, Marezio

et al.

(1990); 4, Marezio (1991); 5,

Chaillout

et al.

(1991).

3212

(Sno.67Lao.24Bao.o9)3(Bao.86Lao. 14)2Lal Cu2011

A3B2CD2011 ,

tP19, (123)

P4/mmm-i2h3 gcba

-02D-C-.O2D-BO-O2A-A

O-O2A-BO-

SnzLazBazCu2Oll, n.s., PN,

R B

-- 0.103 (Anderson

et aL,

1992)

(123)

P4/mmm,

a = 3.9893, c = 16.232A, a Z -- 1

Fig. 31

392

Chapter 8: Crystal Structures of High-T o Superconducting Cuprates

Atom WP PS x y z Occ.

La(1)b l(a) 4/mmm

0 0 0

1 1 0.1307

Sn 2(h)

4mm ~

Ba c 2(g)

4mm 0 0

0.2756

1 1 0.3903

Cu 2(h)

4mm ~

1

La(2) l(b)

4/mmm 0 0

1 1 0

O(1) l(c)

4/mmm ~

0(2) 8(s) . m. 0 0.4106 0.1189

1 1 0.2534

0(3) 2(h)

4mm ~

0(4) 8(s) . m. 0 0.4830 0.4033

0.5

a

Average structure, additional reflections indicate superstructure (~/2a, ,r 6c).

6La(1) = Lao.72Ba0.28.

C Ba = Ba0.86La0.14 .

Compound a (A) c (A) T c (K) Ref.

TizNdzBazCuzO 11 3.90951 15.744 n.s. 1

Ti2 Tb2Ba2Cu2011 3.8769 15.7322 n.s. 2

SnzLazBazCuzO11 3.9893 16.232 a n.s. 3

a

Additional reflections indicate superstructure (~/2a, ~/2a, 6c).

bReferences: 1, Jennings and Greaves (1994); 2, Palacin

et al.

(1995); 3, Anderson

et al.

(1992).

The superconducting (Pb,Cu)-3212 compound Pb2Sr2Yo.5Cao.sCu308

(T c --68 K) was reported by Cava

et aL

(1988), the structure being refined on

nonsuperconducting Pb2Sr2.24Ndo.76Cu308 in space group

Cmmm.

Subramanian

et al. (1989)

described the average structure of Pb2Sr2Yo.75Cao.25Cu308 in space

group

P4/mmm

(a = 3.813, c = 15.76A) with the O site in the PbO layers

displaced from the ideal position (from 2(g) 0 0 0.11 into 8(s) 0.12 0 0.116). The

structure of Pb2Sr2YCu308 was also refined in space group

Cmmm

(Cava

et aL,

1989); however, weak reflections that violate the C-centering are observed for

most compounds. Space group P2212 was used by Fu

et aL

(1989) to refine the

structure of the same compound, whereas other authors reported refinements in

the monoclinic space group

P21/m

(Fujishita

et aL,

1990, 1993). In the structure

of superconducting Pb2Sr2Yo.73Cao.27Cu307.8, refined in space group

Pman,

the

lead atoms are 4-fold coordinated by oxygen atoms (Chaillout

et al.,

1991),

whereas in the structure proposed by Cava

et al.

(1989) the lead atoms have

three closest neighbors, forming ~-tetrahedra. Like (Pb,Cu)-3201,

Pb2Sr2Yl_xCaxCu308+ 6 can be oxidized, and a miscibility gap was observed

between 6- 0 and 1. The average structure of oxidized, nonsuperconducting

Pb2Sr2YCu309.47 was reported in space group

Pmmm

(Marezio

et al.,

1990;

Marezio, 1991), the proposed superstructure (4a, 2b, c) corresponding to an

ordered arrangement of O sites in the

additional

layers. Superconductivity up to

70 K was reported for Ca-free samples of composition Pb2Sr2RCu308 (R = Y,

Nd, Eu, Dy, Ho, Er, Yb, and Lu) prepared under appropriate conditions (Prasad

et

aL,

1990; Xue

et aL,

1993).

H.

Crystallographic Data Sets 393

A superconducting iodine-intercalated (Bi,I)-3212 compound with T c =

80 K (57K in Koike

et al.,

1993), (BizI)SrzCaCuzOy (a- 5.40, c- 19.02 A),

was reported by Xiang

et al.

(1991).

Besides Pb-based cuprates, nonsuperconducting compounds contain-

ing Sn or Ti and a rare-earth element in the

additional

layers have been

reported to crystallize with a 3212 structure. For the structural refinement on

Ti2Nd2Ba2Cu2011 partial disorder of Ti and Cu was considered (Jennings and

Greaves, 1994), whereas for Ti2Tb2Ba2Cu2Ola ((Ti2Tb)Ba2TbCu2011) no

disorder was detected (Palacin

et al.,

1995).

3222

(Pbo.67Cuo.33)3Sr2(Ceo.soPro.5o)2Cu201o

A3B2C2D201o ,

ti38,

(139)

I4/mmm-ge6da

-002--~ C-02-C o---02

D-BO-OA-A .-OA-BO-

Pb2SrzCePrCu3010, n.s., PN,

R B

-- 0.081 (Rouillon

et al.,

1993)

(69)

Fmmm,

a -- 5.4512, b = 5.4799, c = 37.0107 A, Z = 4

Fig. 32

a 1 -I.-a 2, --a 1 --F a 2, c

394

Chapter 8: Crystal Structures of High-T~ Superconducting Cuprates

Atom WP PS x y z Occ.

Cu(1) a 4(a)

mmm 0 0 0

1 0 0.0475

Pb a 8(i)

mm2

Sr a 8(i) mm2 0 0 0.1184

1 0 0.1665

Cu(2) 8(i)

mm2

Ce b 8(i) mm2 0 0 0.2146

O(1)c 32(p) 1 0.0608 0.0693 0.0491

1 0 0.1050

O(2) 8(i)

mm2

1 1 0.1717

0(3) 16(/) . .2 ~

1 1 1

0(4) 8(f) 222 ~ ~

0.25

a Full occupation confirmed.

b Ce = Ceo.5oPr0.50.

c Full occupation confirmed (ignoring site splitting).

Compound a (A) b (A)

c (h) T~ (K) Ref.

PbaSrzCePrCu30 lO 5.4512 5.4799 37.0107 n.s.

Pb2Sr2CeNdCu3Olo.2 5.442 5.462 36.90 n.s.

PbzSrzCeo.67Sm1.33Cu309.8 5.4299 5.4583 36.93 n.s.

PbzSrzCeo.67Eu 1.33Cu3010+6

a

5.423 5.452 36.96 24 b

a Nominal composition.

b Superconducting fraction < 3%.

References: 1, Rouillon

et al. (1993); 2, Rouillon et al. (1990a); 3, Kharlanov et al. (1990).

3222

(Tio.67Ndo.27Bao.o6)3(Bao.92Ndo.o8)2(Ceo.5oNdo.5o)2Cu2013

A3B2C2D2013,

ti44, (139) I4/mmm-g2eSdba

-002-~ C-02-C.-02D-BO-O 2A-A0--02A-BO-

TizNdzBazCeCu2013, n.s., PN, RT, R, = 0.1129

(Den

et al., 1995)

(139)

I4/mmm, a = 3.89978, c = 36.9624A, Z = 2 Fig. 33

H. Crystallographic Data Sets

395

Atom WP PS

Occ.

Nd a 2(a) 4/mmm 0

1

Ti 4(e) 4mm

Bab 4(e) 4mm 0

1

Cu 4(e) 4mm

CeC 4(e) 4mm 0

1

O(1) 2(b) 4/mmm

0(2) 8(g) 2mm . 0

1

0(3) 4(e) 4mm

0(4) 8(g) 2mm . 0

0(5) 4(d) 4m2 0

0

0.05459

0.11362

0.16751

0.21500

0

0.04959

0.10445

0.17293

1

_

4

aNd = Nd0.83Bao.17.

b Ba = Bao.92Nd0.08.

c Ce = Ce0.sNdo. 5.

Compound a (A) c (A) T c (K) Ref.

Ti2Nd2Ba2CeCu2013 3.89978 36.9624 n.s. 1

Ti2Gd2Ba2CeCu2013 3.881 36.972 n.s. 2

References: 1, Den et al. (1995); 2, Li (1995).

(Pb,Cu)-3222 compounds were first reported for the composition

Pb2Sr2CeRCu3010+6 ((Pb2Cu)Sr2(Ceo.sR0.5)2Cu2010+6, R = La, Pr, Nd and

Sm) (Rouillon

et al.,

1990a). The crystal structure was refined on the Nd-

containing compound in space group

Fmmm.

Pb2Sr2Ceo.67R1.33Cu3010+, 5

compounds with R--La, Pr, Nd, Sm-Tm were reported by Kharlanov

et al.

(1990), who claimed superconductivity for the Eu-containing sample. Splitting of

the Pb and O sites in the PbO layers was considered in the structural refinement

carried out on the Sm-containing compound (Pb in 16(n) 0.547 0 0.0487 and O

in 16(m) 0 0.15 0.052). Further splitting of the O site was proposed by Rouillon

et al.

(1993).

Superconductivity up to 12 K was observed for a bromine-intercalated

(Bi,Br)-3222 compound,

(Bi2Bro.12)Sr2Ceo.36Gdl.64Cu2010+6

(Koike

et al.,

1994).

Like the Ti-based 3212 compounds, the 3222 compounds with Ti and rare-

earth elements in the

additional

layers are nonsuperconducting.

Poole Ch.P., Jr. Handbook of Superconductivity

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