Online-only Table 2 New high quality ferroelectric candidates and their space groups, polarizations and band gaps.

Ag₁₀Br₃Te₄

36

63

3.9

0.9

1

Ag₂O₄W

34

58

1

1.8

4

Ag₂S

4

11

21.1

0.4

5

64

17.6

0.4

7

36

63

0.4

1.4

9

AgAl₁₁O₁₇

40

63

2.4

3.1

15

AgC₂O₂

5

15

0

1

17

AlCH₂NaO₅

46

74

0.8

5

25

AlCl₄Hg₂Sb

33

60

0.5

0.9

26

AlH₃O₃

1

2

0.1

5

32

Hydroxyl

7

61

8.1

5

33

AlN

186

194

133

4.1

38

AuCl₄K

7

14

0.3

1.4

43

B₁₃C₂Li

44

74

0.8

2.6

45

B₂O₆Zn₃

9

15

0.1

2.7

47

Ba₂F₇Y

4

14

0.7

6.5

57

BaC₂CaO₆

4

11

0

4.8

59

BaCO₃

4

11

1

4.5

60

Carbon-oxygen compound

BaCl₅La

4

62

26.1

4

61

BiCuO₈W₂

1

2

0.8

1.3

86

BiO₃Y

185

194

9.7

2.1

96

Hexagonal manganite-like

Br₃CsGe

8

221

19.3

1.7

97

C₂HO₂

6

11

3.4

2.8

106

Carbon-oxygen compound

C₂HgN₂S₂

5

12

0.9

2.1

107

C₆Cu₂H₁₀N₄S₃

4

14

0

2.8

109

CCs₄O₄

146

215

1.7

1.6

110

Carbon-oxygen compound

CH₄N₂S

26

62

4.8

3.3

111

CHO₂Tl

33

52

0.8

3.5

112

Carbon-oxygen compound

CK₄O₄

5

121

16.7

2

113

Carbon-oxygen compound

16.6

2

114

8

121

10.2

2.2

115

146

215

2.6

2.3

116

160

215

14.6

1.9

117

CLi₄O₄

5

121

49

5

118

Carbon-oxygen compound

49

5

119

0.1

4.8

120

160

215

16.6

4.2

121

CN₂Pb

33

62

10.5

1.9

122

CNa₄O₄

5

121

39.2

2.2

123

Carbon-oxygen compound

39.2

2.2

124

8

215

12.6

1.7

125

146

215

3.6

1.9

126

56.2

2.2

127

CO₄Rb₄

5

23

14.6

1.4

128

Carbon-oxygen compound

121

14.6

1.4

129

14.6

1.4

130

146

215

0.6

1.7

131

160

215

42.8

0.4

132

Ca₅ClO₁₂P₃

173

176

2.1

5.4

138

CaF₂

26

123

16.5

6.3

139

Fluoride

Cd₂ClP₃

9

15

0.8

1.3

144

CdCl₂

5

12

48.4

3.1

145

Cl₄GaHg₂Sb

33

60

0.5

0.8

162

ClH₃O₅

33

62

5.2

5.4

172

ClH₄NO₄

33

62

2.2

5.3

173

ClIn

36

63

3.8

1.4

174

CrO₃

33

62

0.4

1.6

188

CrO₉P₃†

9

15

0.3

3.2

191

Cs₂HgI₄

4

11

0.3

2.1

192

Cs₂N₂Tb₆Te₇

8

12

0.2

0.8

193

Cs₂O₃Pb

36

63

7.2

1.4

194

CuI

7

216

0

1.2

204

Er₂F₇K

33

62

1.5

6.9

210

Fluoride

F₂HRb

46

140

1.6

6.7

212

Fluoride

F₂Pb

41

225

5

4.4

213

Fluoride

F₃Nd

185

193

17.6

7.7

214

Fluoride

F₃PbRb

9

221

4

3.8

215

Perovskite

F₅V

9

15

1

2.8

223

Fluoride

29.7

3.3

224

F₆LiV

33

225

1.3

3.2

225

Fluoride

FTl

39

225

6.4

3.1

229

Fluoride

GaLuO₃

185

194

8

2.9

249

Hexagonal manganite-like

GaN₅O₁₄

5

82

0

1.3

252

GaO₃Sc

185

194

10

3.2

253

Hexagonal manganite-like

H₂Mg

29

60

30.9

2.4

258

H₂MoO₄

1

2

0.2

3.2

260

39.2

2.5

261

16.3

2.1

262

H₂O₁₀U₃

1

2

23

1.8

266

23

1.8

267

H₂O₂Sr

26

62

1.2

4

268

Hydroxyl

1.2

4

269

H₂O₄S

5

15

20.4

6.1

272

Hydroxyl

9

15

51

5.8

273

H₂O₄Sn₃

9

114

1.6

2.5

275

Hydroxyl

H₂O₄U

36

64

2.9

1.9

277

Hydroxyl

2.9

1.9

278

H₃LaO₃

173

176

17.9

4

279

Hydroxyl

H₃O₃Pr

6

11

0.1

3.8

280

Hydroxyl

176

0.1

3.8

281

H₃O₃Y

173

176

7.7

3.9

282

Hydroxyl

H₃O₄P

7

14

4.1

5.7

283

4.1

5.7

284

H₄O₅S

7

14

1

5.7

286

H₅IO₆

7

14

0.3

2.3

289

HInO₂

31

58

13.2

1.8

293

Hydroxyl

HK₂NO₆S₂

9

15

3.2

5.3

294

HNaO

4

11

10.7

3

295

Hydroxyl

63

10.7

3

296

HORb

4

11

10.5

3.4

300

Hydroxyl

ILi₆PS₅

9

216

2.6

2.3

304

K₂O₇Zn₆

102

136

2.5

0.8

310

K₃S₄Sb

36

217

1

2.2

311

KLaS₄Si

4

11

7.4

2.8

312

LiO₁₂P₃Zr₂

5

167

8

4.2

341

LiO₄PV^†

33

60

0.1

2.7

342

MgN₂O₆

29

205

0.7

3.5

345

MoO₃

7

62

4.7

1.9

353

N₂O₆Zn

29

205

1.1

3.3

356

N₃Na

5

12

51.8

4.1

357

NbO₅P

33

62

4

2.3

366

O₂₃Rb₆Si₁₀

38

189

0.1

4.3

370

0.5

4.2

371

O₂Si

4

20

0

5.4

373

182

0

5.4

374

0.4

5.6

375

8

12

0

5.5

378

9

194

0.1

5.5

379

36

63

0.2

5.7

383

0

5.6

384

64

0.2

5.4

385

44

119

0

5.7

386

O₃SbY

185

194

7.5

1.5

391

Hexagonal manganite-like

O₃ScY

185

194

6.6

3.1

392

Hexagonal manganite-like

O₃Te

185

194

0

0.5

394

OPb

29

57

54.3

2.2

409