無機結構化學Inorganic Structural Chemistry

李光華

2008, 4, 16

Two close-packed layers

T

O

T: tetrahedral site O: octahedral site

Close-packed layer

Close-packed layer

O layer

T+ layer

T- layer

Two close-packed layers

A

A

B

六方最密堆積 (hexagonal close-packing, hcp)

其他最密堆積 ．．． ABCACB．．． ．．． ABAC．．．

立方最密堆積 (cubic close-packing, ccp)

3-fold axis 3-fold axis

A

B

C

A

六方最密堆積

• Rock salt, NaCl• Nickel arsenide, NiAs

• Fluorite, CaF2

• Zinc blende, ZnS • Wurtzite, ZnS

• CdCl2

• CdI2

• CrCl3

一些常見的基本結構

Rock Salt (NaCl)

Nickel Arsenide, NiAs

Zinc Blende (ZnS)

Fluorite (CaF2)

Fluorite, orange river

Rutile (TiO2)

Perovskite (SrTiO3)

K2NiF4

(La1.87Ba0.13)CuO4

YBa2Cu3O7-x

YBa2Cu3O7

Zeolites （沸石） are crystalline, hydrated aluminosilicat

es with open 3D framework structures built of [SiO4]4- an

d [AlO4]5- tetrahedra linked to each other by sharing the

oxygens to form regular intracrystalline cavities and ch

annels of molecular dimensions.

Scolecite

CaAl2Si3O10·3H2O

Si

Faujasite(Na2,Ca,Mg)29[Al58Si134O384]·240H2O

Cubic, Fd3m, a = 24.7 Å

Faujasite has large openings (12 tetrahedra around the ring, opening of 7.4 Å) and has many commercial uses in catalysis, ion exchange and gas sorption.

24

UTD-1 CIT-5 (Balkus, K. J. et al. J. Porous Mater. 1995) (Davis, M. E. et al. Chem. Commun. 1997)

Zeolites

Mixed octahedral-tetrahedral

framework oxides

Metal phosphates and silicates

Synthetic Methods:

High temperature solid state reaction (phosphates, silicates)

Mild hydrothermal reaction (phosphates, silicates, organic-inorganic hybrid compounds)

High-temperature, high-pressure hydrothermal reaction (phosphates, silicates)

Flux synthesis (phosphates, silicates)

Ionothermal synthesis (phosphates, organic-inorganic hybrid compounds)

Microwave-assisted hydrothermal synthesis (phosphates, silicates, organic-inorganic hybrid compounds) Vapor phase transport method (phosphates)

X光單晶繞射儀 (X-Ray Single-Crystal Diffractometer)

• The method is particularly suited for the

synthesis of phases that are unstable at

higher temperature.

• It is also a useful technique for growth of

single crystals.

Hydrothermal methods （水熱法）

374 , ℃ 217 atm

25 200 250 340 360 373 >374 ºCgas

liquid

80% fill

50% fill

32% fill(critical fill)

10% fill

seeds

baffle

nutrient

Dissolving temperature: 400 ºCCrystallizing temperature: 360 ºCDegree of fill: 80%Solution: 1.0 M NaOHBaffle opening: 5%Pressure: 21,000 psi

Schematic of Hydrothermal System

Crystal growth conditions for SiO2

Teflon-lined autoclave

An Organically Templated Iron Phosphate[H3N(CH2)3NH3]2[Fe4(OH)3(HPO4)2(PO4)3]·xH2O (a 20-ring FeIII phosphate)

Chem. Commun. 1997.

[Ga2(N3C4H13)(PO4)2]·2H2Oa 24-ring Ga phosphate

J. Am. Chem. Soc, 2001

(C4H9NH3)2[AlFZn2(HPO3)4]

A Novel Nanoporous Structure with helical 26R channels

J. Am. Chem. Soc. 2007.

500-600 ºCPercent fill 55-70%~1100-2000 bars

The autoclave used for high-T, high-P hydrothermal synthesis

gold ampoule

a

b

c

K(UO)Si2O6: A Pentavalent Uranium SilicateP4/mbm, a = 9.1428(3), c = 8.2587(6) Å

2.070 Å

2.060 Å

2.164 Å

U 4f XPS: U 4f7/2, 380.7 eVmagnetic susceptibility: eff = 1.32 B/mol at 300 K

J. Am. Chem. Soc. 2005

K(UO)Si2O6

K3(U3O6)(Si2O7) and Rb3(U3O6)(Ge2O7)A Pentavalent-Uranium Silicate and Germanate

P62c, a = 9.5389(5) Å, c = 8.3389(9) Å for the silicate

_

d(U-O): 2.087-2.190 Å

Inorg. Chem. 2008

U(1)6+: d(U=O): 1.830 Å, d(U-O): 2.242~2.250 Å

U(2)6+: d(U=O): 1.841 Å, d(U-O): 2.208~2.263 Å

U(3)5+:d(U-O): 2.009~2.230 Å

Rb3(U2O4)(Ge2O7): A Mixed-Valent Uranium Germanate

P21/n, a = 6.9755(5) Å, b = 12.2284(8) Å, c = 15.399(1) Å, = 00.560(1)°

無機固態化合物的合成與結構化學是一個具有高度學術價值與應用前景的領域，它涵蓋的化合物非常廣泛，包括高

溫超導銅氧化物、 MgB2 超導體、巨磁阻錳氧化物、磷酸

鈦倍頻晶體、鋁矽酸鹽觸媒材料…等。目前我們仍無法仿效有機化學家設計合成這些無機固態化合物，即使合成得到並且得知該化合物的組成與結構，也通常不易或無法預測它們的化性與物性。這是個充滿機會與驚喜的研究領域，回想我自研究生開始便從事無機固態化合物的合成與結構化學之研究，這 20 多年來雖然換過幾個研究課題，但是我對此領域的好奇與喜悅心情與當年比較絲毫不減。

總結