Martienssen W., Warlimont H. (Eds.). Handbook of Condensed Matter and Materials Data

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922 Part 4

070

140

120

100

30 40 50 60

T (K)

(A m

–1

)

=20×10

–1

 [110]

[110]

1.0

0.5

0 50 100 150 200 250 300

T (K)

'''

κκ

19.93

19.66

60 65

100 kHz

T (K)

21.60

21.15

1 MHz

T (K)

55 60 65

Fig. 4.5-46 Ni

I. κ



and κ



versus T . f =

100 kHz. The insets show details of κ



versus T at 100 kHz

and 1 MHz around Θ

Fig. 4.5-45 Ni

I. σ

versus T. σ

is the remanent

magnetization. The sample was cooled down to 4.2K in

a magnetic ﬁeld of 1.6×10

A/m parallel to [100] prior to

the measurement

take place simultaneously. There is a magnetoelec-

tric effect, where the magnetic polarization is reversed

by reversal of the electric polarization and vice

versa.

4.5.4.2 Inorganic Crystals

Other Than Oxides [5.3]

SbSI Family

SbSI (LB Number 20A-7). SbSI is ferroelectric be-

low 20

◦

C. The phase transition is of the displacive

type, a relatively rare characteristic in nonoxide ma-

terials. The crystal is photoconductive (Figs. 4.5-47 and

4.5-48).

BaMnF

Family

BaMnF

(LB Number 26A-2). This crystal exhibits a di-

electric anomaly at about 242 K (Fig. 4.5-49). The

coercive ﬁeld is very large. The crystal is antiferromag-

netic below 25 K (Fig. 4.5-50). The dielectric constant

varies depending upon the magnetic ﬁeld at low tem-

peratures (Fig. 4.5-51).

10 20 30 40 50 60

T (°C)

f = 1 kHz

2.0

1.5

1.0

0.5

(10

))(10

–4

)

(1/

Fig. 4.5-47 SbSI. κ

and 1/κ

versus T

Part 4 5.4

Ferroelectrics and Antiferroelectrics 5.4 Physical Properties of 43 Representative Ferroelectrics 923

5101520

T (°C)

(10

–2

C m

–2

)

Fig. 4.5-48 SbSI. P

versus T

300

8.8

8.6

8.4

8.2

50 100 150 200 250

T (K)

f = 100 kHz

Fig. 4.5-49 BaMnF

. κ

and κ

versus T

350

300

250

200

150

100

50 100 150 200 250 300

T (K)

(10

–9

/mol)

magn m

⊥



⊥

Fig. 4.5-50 BaMnF

. χ

magn m

versus T . χ

magn m

is the

magnetic susceptibility, and χ

⊥

and χ



are the magnetic

susceptibilities measured perpendicular and parallel, re-

spectively, to the b axis

12.095

12.090

12.085

12.080

12.075

12.070

12.065

20 22 24 26

T (K)

f = 9.75 kHz

H = 8.36 ×10

A/m

2.51 ×10

A/m

H = 0

Fig. 4.5-51 BaMnF

. κ

versus T . Parameter: magnetic

ﬁeld H. f = 9.75 kHz

Part 4 5.4

924 Part 4

HCl Family

HCl (LB Number 27A-1). This crystal is ferroelectric be-

low 98 K. The chemical formula is the simplest one

among all known ferroelectrics. The coercive ﬁeld is

large (Figs. 4.5-52 and 4.5-53).

80 100 120 140 160 180 200

T (K)

melt

Fig. 4.5-52 HCl (polycrystalline). κ

versus T . κ

is the

static dielectric constant

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.97 0.98 0.99 1.00 1.01 1.02 1.03

(10

–2

C m

–2

)

Fig. 4.5-53 HCl. P

versus T/Θ

obtained from

pyroelectric-current measurement. Θ

= 98 K

Fig. 4.5-55 NaNO

. P

versus T , determined by

pyroelectric-charge measurement

NaNO

Family

NaNO

(LB Number 28A-1). This crystal is ferroelectric

below 163.9

◦

C (Figs. 4.5-54 and 4.5-55). The sponta-

neous polarization results from orientational order of

the NO

−

ions. Between 163.9 and 165.2

◦

C, the crystal

structure is incommensurately modulated with a wave

vector δa

∗

, where δ varies from 0.097 to 0.120 with

increasing temperature.

120 130 140 150 160

170 180 190

f = 10 kHz

T (°C)

Fig. 4.5-54 NaNO

. κ

,κ

,andκ

versus T

180

30 60 90 120 150

(10

–2

C m

–2

)

T (°C)

Part 4 5.4

Ferroelectrics and Antiferroelectrics 5.4 Physical Properties of 43 Representative Ferroelectrics 925

0 20025 50 75 100 125 150 175

II III I

f = 100 kHz

T (°C)

Fig. 4.5-56 KNO

. κ

versus T

10.0

7.5

5.0

2.5

115.0 117.5 120.0 122.5 125.0 127.5 130.0

(10

–2

C m

–2

)

T (°C)

Fig. 4.5-57 KNO

. P

versus T

KNO

Family

KNO

(LB Number 30A-2). This crystal is ferroelectric

between about 115 and 125

◦

C in a metastable phase III

which appears on cooling. Hydrostatic pressure stabi-

lizes this phase (Figs. 4.5-56 and 4.5-57).

KDP (KH

) Family

(KDP) (LB Number 33A-1). KH

is a clas-

sical and extensively studied ferroelectric crystal. It is

ferroelectric below 123 K (Figs. 4.5-58 and 4.5-59). The

transition is a typical ferroelectric phase transition, re-

lated to a conﬁguration change in a three-dimensional

hydrogen-bond network. Figures 4.5-61 and 4.5-60

demonstrate changes in the proton conﬁguration asso-

ciated with the phase transition. The transitions related

50 100 150 200 250 300

T (K)

Fig. 4.5-58 KH

. κ

and κ

versus T . f = 800 Hz

1.25

1.00 0.75 0.50 0.25 0

–T (K)

(10

–2

C m

–2

)

Fig. 4.5-59 KH

. P

versus (Θ

−T). Θ

= 123 K

to hydrogen atom rearrangement in the hydrogen-bond

network are characterized by sensitivity to deuter-

ation and hydrostatic pressure, as demonstrated in

Figs. 4.5-62 and 4.5-63, respectively. For theoretical

studies of the phase transition, readers should refer

to [5.7]. The crystal is useful in nonlinear optical

devices.

CsH

(LB Number 33A-3). This crystal is ferroelec-

tric below about 151.5 K. The crystal system of its

paraelectric phase (monoclinic) is different from that

of KH

(tetragonal). The temperature dependence

of the dielectric constant above the Curie point deviates

considerably from the Curie–Weiss law, suggesting that

the transition is related to one-dimensional ordering of

hydrogen atoms in a hydrogen-bond network. Deuter-

ation changes the transition temperature from 151.5to

264.7 K (Fig. 4.5-64).

Part 4 5.4

926 Part 4

K,P

O(1)

O(2)

O(1)

K,P

O(2)

Fig. 4.5-60 KH

. Fourier map of the projection of

the proton distribution on (001) in the ferroelectric phase

(77 K), determined by neutron diffraction. The proton dis-

tribution lies approximately on a line joining two oxygen

atoms O(1) and O(2) and closer to O(1)

0.2 Å

c) d)

+ 2K

– 1.3 K

– 20 K

– 10 K

Fig. 4.5-61a–d KH

. Change of proton distribution

above and below the Curie point Θ

, determined by neutron

diffraction. Contours are all equally spaced.

(a) Θ

+2K;

(b) Θ

−1.3K;(c) Θ

−10 K; (d) Θ

−20 K

100

110110 130 150 170 190 210 230 250

T (K)

(10

)

x =0

0.08

0.17

0.29

0.46

0.78

f = 3 kHz

Fig. 4.5-62 KH

2(1−x)

. κ

versus T . Parameter: x

RbH

-NH

(LB Number 33B-5). The mixed

crystals Rb

1−x

(NH

)

, where 0.2 < x < 0.8,

show a characteristic temperature dependence of the di-

electric constants, suggesting that at low temperatures

0 18020 40 60 80 100 120 140 160

T (K)

(10

)

p=1.8×10

8.4 ×10

15.4 ×10

16.9 ×10

19.3 ×10

21.0 ×10

Fig. 4.5-63 KH

. κ

versus T . Parameter: hydrostatic

pressure p

Part 4 5.4

Ferroelectrics and Antiferroelectrics 5.4 Physical Properties of 43 Representative Ferroelectrics 927

100

150 200 250 300

T (K)

x = 0

x = 0.03

x = 0.15

x = 0.57

Fig. 4.5-64 CsH

and CsH

2(1−x)

. κ

versus

T . Parameter: x

0 100

'''

T (K)

f =

6.0 MHz

31.6 MHz

218.8 MHz

1000.0 MHz

Fig. 4.5-65 Rb

0.65

(NH

)

0.35

. κ



and κ



versus T .

Parameter: f

a local order becomes predominant in a conﬁguration of

hydrogen atoms without deﬁnite long-range order, i. e.

a dipole glass state develops (Fig. 4.5-65).

PbHPO

Family

PbHPO

(LB Number 34A-1). This crystal is ferroelec-

tric below 37

◦

C (Figs. 4.5-66 and 4.5-67). It exhibits

T(K)

0 360

60 120 180 240 300

f = 1592 Hz

(100)

Fig. 4.5-66 PbHPO

. κ

(100)

,κ

,andκ

versus T . κ

(100)

the dielectric constant perpendicular to the (100) plane

(10

–2

C m

–2

)

T (°C)

–60 60

2.0

1.6

1.2

0.8

0.4

0.15

0.12

0.09

0.06

0.03

–40 –20 0 20 40

p (10

–2

C/K m

)

Fig. 4.5-67 PbHPO

. P

and p versus T , measured on

(100) planar specimen. p =−dP

/dT is the pyroelectric

coefﬁcient

characteristic critical phenomena, suggesting that the

spontaneous polarization results from an ordered ar-

rangement of hydrogen atoms in a one-dimensional

array of hydrogen bonds.

(NH

)

Family

(NH

)

(LB Number 39A-1). This crystal is fer-

roelectric below −49.5

◦

C. The dielectric constant

is practically independent of temperature above the

Curie point (Fig. 4.5-68). The spontaneous polarization

changes its sign at about −190

◦

C (Fig. 4.5-69), sug-

gesting a ferrielectric mechanism for the spontaneous

polarization.

Part 4 5.4

928 Part 4

T (°C)

–200

100

150

–150 –100 –50 0

5 ×10

V m

–1

f = 10 kHz

Fig. 4.5-68 (NH

)

. κ

versus T

0.7

0.6

0.5

0.4

0.3

0.2

0.1

–0.1

–260 –230 –200 –170 –140 –110 –80 –50 –20

T (°C)

(10

–2

)

0.62

0.61

0.60

0.59

0.58

–60 –55

T (°C)

–50

Fig. 4.5-69 (NH

)

. P

versus T

(NH

)HSO

Family

(NH

)HSO

(LB Number 40A-5). This crystal is ferroelec-

tric in the temperature range between −119 and −3

◦

(Figs. 4.5-70 and 4.5-71).

(NH

)LiSO

Family

(NH

)LiSO

(LB Number 41A-5). This crystal is ferroelec-

tric in the temperature range between 10 and 186.5

◦

(Figs. 4.5-72 and 4.5-73).

(NH

)

H(SO

)

Family

(NH

)

H(SO

)

(LB Number 42A-1). This crystal is fer-

roelectric in its phase VII below −211

◦

C. Another

Fig. 4.5-72 NH

LiSO

. κ

and κ

versus T . f = 3kHz

–200 50

1450

–150

–100 –50 0

1400

200

150

100

T (°C)

Fig. 4.5-70 NH

HSO

. κ

versus T . f = 10 kHz

–125

0.8

0.4

–100 –75 –50 –25 0

T (°C)

(10

–2

)

Fig. 4.5-71 NH

HSO

. P

versus T

0 200

50 100 150

T (°C)

Part 4 5.4

Ferroelectrics and Antiferroelectrics 5.4 Physical Properties of 43 Representative Ferroelectrics 929

0.8

0.6

0.4

0.2

40 80 120 160 200

T (°C)

(10

–2

)

Fig. 4.5-73 NH

LiSO

. P

versus T

0912345678

(°C)

140

120

100

–20

–40

–60

–80

–100

p (10

Pa)

III

VII

Fig. 4.5-74 (NH

)

H(SO

)

. T versus p phase diagram.

p is the hydrostatic pressure. Phases VI and VII are ferro-

electric

Fig. 4.5-76 (NH

)

(SO

)

. κ



[100]

and κ



[100]

versus T

–200 0

2.5

2.0

1.5

1.0

0.5

–175 –150 –125 –100 –75 –50 –25

T (°C)

(10

–2

C m

–2

)

x = 0.40

x = 0.93

x = 0.90

VII

Fig. 4.5-75 ((NH

)

1−x

((ND

)

(SO

)

. P

versus

T . Parameter: x. Gray circles (for Phase VI), determined by

pyroelectric measurements. Brown circles (for phase VII),

determined by hysteresis loop measurements

ferroelectric phase, VI, is induced by hydrostatic pres-

sure (Fig. 4.5-74). When H is substituted by D, phase VI

appears at atmospheric pressure and the temperature of

the transition to phase VII becomes higher. Figure 4.5-75

–200 140

–190 –180 –170 –160 –150

0.4

0.3

0.2

0.1

T (°C)

[100]

bias

2000 kV m

–1

3.3 GHz

at 10 kHz

(600 V m

–1

)

[100]

Part 4 5.4

930 Part 4

80 94

0.8

0.6

0.4

0.2

82 84 86 88

90 92

(10

–2

)

T (K)

Fig. 4.5-77 (NH

)

(SO

)

. P

versus T

–186

–184 –182 –180 –178 –176 –174

T (°C)

(10

–2

)

Fig. 4.5-78 (NH

)

(SO

)

. Q

versus T. Q

is the

electrostrictive constant

shows temperature dependence of P

for three values

of x in ((NH

)

1−x

((ND

)

(SO

)

Langbeinite-Type Family

(NH

)

(SO

)

(LB Number 43A-13). This crystal is fer-

roelectric below about −184

◦

C. The dielectric constants

are insensitive to temperature above the transition point

(Fig. 4.5-76), and the spontaneous polarization does not

depend upon temperature (Fig. 4.5-77). The electrostric-

tive constant Q

, however, exhibits an anomaly at the

transition point (Fig. 4.5-78).

4.5.4.3 Organic Crystals, Liquid Crystals,

and Polymers [5.4]

SC(NH

)

Family

SC(NH

)

(LB Number 50A-1). This crystal exhibits at

least ﬁve phases, I, II, III, IV, and V (Figs. 4.5-79

0 300

100 140 180 220 220

T (K)

III

f = 1 kHz

E = 10 V m

–1

Fig. 4.5-79 SC(NH

)

. κ

versus T

165

170 175 180 185 190 195 200

bias

(10

V/m)

T (K)

(Ferro-

electric)

Inc.

(Para-

elec-

tric)

δ =

–

III (δ=

–

)

Method

Pyroelectric response

Hysteresis loops

Dielectric constant

Polarization

Inc.

Fig. 4.5-80 SC(NH

)

. E

bias

versus T phase diagram.

The value of δ means that the phase is commensurately

modulated with a vector of wavenumber δc

∗

. Inc., incom-

mensurate phase

Part 4 5.4

Ferroelectrics and Antiferroelectrics 5.4 Physical Properties of 43 Representative Ferroelectrics 931

3.0

2.5

2.0

1.5

1.0

0.5

110 130 150 170

T (K)

(10

–2

)

Fig. 4.5-81 SC(NH

)

. P

versus T for phase V

and 4.5-80). The crystal is ferroelectric in phase V

(Fig. 4.5-81), and slightly ferroelectric with a very

small spontaneous polarization in phase III. The crystal

structure is modulated commensurately or incommen-

surately except for phases I and V, as indicated in

Fig. 4.5-80.

DSP (Ca

Sr(CH

COO)

) Family

Sr(CH

COO)

(DSP) (LB Number 58A-1). This crys-

tal is ferroelectric below about 4

◦

C (Fig. 4.5-82). The

Curie–Weiss constant is small (60 K). Critical slowing-

down (see Sect. 4.5.3) takes place (Fig. 4.5-8).

–25 10

0.3

0.2

0.1

–20 –15 –10 –5 0 5

T (°C)

(10

–2

)

–160

–120 –80 –40 0 40 80

f = 10 kHz

T (°C)

Fig. 4.5-83 (NH

COOH)

· H

. κ



,κ



,andκ



versus T . These quantities are referred to the unit cell

vectors: a



= a +c, b



=−b,andc



=−c

100

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

125 150 175 200 225 250 275 300 325

T (K)

(10

–2

)

Fig. 4.5-84 (NH

COOH)

· H

. P

versus T . P

is parallel to the b axis. Gray circles: values determined by

pyroelectric measurements. Triangles and brown circles:

determined from hysteresis loop by different authors

Fig. 4.5-82 Ca

Sr(CH

COO)

. P

versus T .The

three curves show the effect of annealing: 1, unannealed; 2,

annealed at 330

◦

C for 60 h; 3, annealed at 330

◦

C for 60 h

and at 390

◦

Cfor5h

Part 4 5.4