hydrothermal synthesis and structural characterization of new lanthanide coordination polymers with...

Hydrothermal synthesis and structural characterization of new lanthanide

coordination polymers with pimelic acid and 1,10-phenanthroline

Liang Huanga,*, Li-Ping Zhanga, Lin-Pei Jinb

aDepartment of Chemistry, Anyang Teachers College, Anyang 455000, ChinabDepartment of Chemistry, Beijing Normal University, Beijing 100875 China

Received 25 November 2003; revised 25 November 2003; accepted 21 January 2004

Abstract

This paper presents three new lanthanide coordination polymers [Pr2(pim)3(phen)2(H2O)]n·3n H2O (1) (H2pim ¼ pimelic acid;

phen ¼ 1,10-phenanthroline) and [Ln(Hpim)(pim)(phen)]n·1.5n H2O (Ln ¼ Nd, 2; Er, 3) prepared by the hydrothermal reaction. The

structural details of complexes 1, 2 and 3 are reported. In complex 1, the Pr(III) ions are bridged by pim in three modes to form 2D layers.

Adjacent layers are assembled by hydrogen bonds and p–p stacking between phen ligands into a 3D network. In complex 2, the Nd(III) ions

are connected by pim and Hpim in two modes into 1D chains. Hydrogen bonding and p–p stacking between chains result in a 3D

supramolecular structure. Single crystal X-ray diffraction analysis shows that complex 3 is isostructural with complex 2.

q 2004 Elsevier B.V. All rights reserved.

Keywords: Lanthanide; Coordination polymer; Hydrothermal synthesis; Crystal structure; Infrared

1. Introduction

In recent years, the design and synthesis of metal–

organic coordination polymers have received increasing

interest because such supramolecular assembly is a central

theme in the design of new materials with unusual structures

and properties [1–3]. The multifunctional rigid ligands such

as 1,2,4,5-benzenetetracarboxylic acid [4], 1,3,5-benzene-

tricarboxylic acid [5], and 1,4-benzenedicarboxylic acid [6]

are used extensively as linkers in constructing coordination

polymers. Despite examples of coordination polymers

containing flexible ligands have appeared in the literature

in recent years, much of the work has so far been focused on

coordination polymers containing transition metal and post-

transition metal elements including Fe, Co, Ni, Cu, Ag, Zn,

Cd, and Hg [7]. Lanthanide metal complexes have been

rarely investigated [8]. In this work, we select pimelic acid

and 1,10-phenanthroline as ligands and adopt hydrothermal

technique to construct new lanthanide complexes with

characteristic structures and get better understanding of

ternary lanthanide complexes with a,v-dicarboxylic acid

and phen [9]. To the best of our knowledge, binary

lanthanide pimelates have been reported [10]. However,

no lanthanide complex containing both the ligands of

pimelic acid and 1,10-phenanthroline has been reported.

Herein, we report the synthesis and crystal structures of three

lanthanide complexes [Pr2(pim)3(phen)2(H2O)]n·3n H2O (1)

and [Ln(Hpim)(pim)(phen)]n·1.5n H2O (Ln ¼ Nd, 2; Er, 3),

which have supramolecular architecture assembled from 1D

chain or 2D layer via hydrogen bonding and p–p stacking.

2. Experimental

2.1. Materials and apparatus

LnCl3·n H2O (Ln ¼ Pr, n ¼ 7; Ln ¼ Nd and Er, n ¼ 6)

were prepared by dissolving their oxides in dilute

hydrochloric acid, respectively, and then dried. All other

chemicals were purchased and used as received without

further purification. C, H and N data were obtained using an

American PE 2400 II CHNS/O elemental analyzer. Infrared

spectra were recorded with an American Nicolet Avatar 360

FT-IR spectrometer.

0022-2860/$ - see front matter q 2004 Elsevier B.V. All rights reserved.

doi:10.1016/j.molstruc.2004.01.027

Journal of Molecular Structure 692 (2004) 169–175

www.elsevier.com/locate/molstruc

* Corresponding author. Tel./fax: þ86-037-22902048.

E-mail address: [email protected] (L. Huang).

http://www.elsevier.com/locate/molstruc

2.2. Preparation of complexes

LnCl3·n H2O (0.3 mmol; Pr, n ¼ 7, 0.1120 g; Nd, n ¼ 6,

0.1076 g; Er, n ¼ 6, 0.1145 g) and H2pim (0.3 mmol,

0.0481 g) were dissolved in 10 ml deionized water,

respectively, to which phen·H2O (0.3 mmol, 0.0595 g) was

added and the pH value was adjusted to about four with

NaOH aqueous solution. The mixture was placed in a

Teflon-lined stainless steel vessel (23 ml). The vessel was

sealed and heated (Pr, at 160 8C for 3 d; Nd, at 150 8C for

3 d and Er, at 190 8C for 3 d) under autogeneous pressure

and then cooled to room temperature. After filtering, the

product was washed with ethanol and then dried under

ambient. Columnlike crystals of the complex 1 were

collected in yield (0.0681 g, 38.2%). After evaporation of

the filtrates for several days at room temperature, rhombus

platelike crystals of the complexes 2 and 3 were obtained,

respectively (yield: 4.9% for 2; 5.1% for 3).

[Pr2(pim)3(phen)2(H2O)]n·3n H2O 1. Found (calcd., %):

C, 45.24(45.46); H, 4.52(4.58); N, 4.26(4.17). IR(KBr

pellet, cm21): 3448(s, br), 3073(w), 3058(w), 2933(m),

2860(w), 1578(vs), 1560(vs), 1421(vs), 1346(w),

1309(w), 1220(w), 1139(w), 1102(w), 1088(w), 848(s),

732(s), 637(m).

[Nd(Hpim)(pim)(phen)]n·1.5n H2O 2. Found (calcd., %):

C, 46.72(46.69); H, 5.21(4.82); N, 4.04(4.19). IR(KBr

pellet, cm21): 3423(m, br), 3059(w), 2934(s), 2860(w),

1718(s), 1596(vs), 1587(vs), 1542(vs), 1424(vs), 1347(w),

1311(w), 1142(w), 1103(w), 1088(w), 850(s), 731(s),

638(w).

[Er(Hpim)(pim)(phen)]n·1.5n H2O 3. Found (calcd., %):

C, 45.37(45.14); H, 4.85(4.66); N, 3.97(4.05). IR(KBr

pellet, cm21): 3386(m, br), 3082(w), 3060(w), 2934(s),

2856(w), 1716(s), 1610(vs), 1554(s), 1439(vs), 1424(vs),

1407(vs), 1346(w), 1310(w), 1283(w), 1259(w), 1209(w),

1105(w), 1091(w), 851(s), 732(s), 635(w).

2.3. Single-crystal X-ray diffraction

Single-crystal X-ray data were collected on a Bruker

SMART 1000 CCD diffractometer equipped with graphite

monochromatized Mo Ka radiation (l ¼ 0:71073 A).

Semiempirical absorption corrections were applied using

the SADABS program. All calculations were carried out

with use of SHELXS-97 and SHELXL-97 programs [11]. The

structures were solved by the direct methods. All structures

were refined on F2 by full-matrix least-squares methods.

The crystallographic data of the complexes are summarized

in Table 1 and the coordination and hydrogen bond lengths

in Table 2.

Table 1

Crystallographic data for complexes 1, 2 and 3

1 2 3

Formula Pr2C45H54N4O16 NdC26H32N2O9.5 ErC26H32N2O9.5

Formula weight 1188.74 668.78 691.80

Crystal system Triclinic Triclinic Triclinic

Space group P�1 P�1 P�1

a (A) 12.267(4) 11.170(3) 11.044(6)

b (A) 13.903(5) 11.720(3) 11.588(6)

c (A) 15.348(5) 12.562(4) 12.608(6)

a (8) 89.008(7) 110.454(5) 110.474(7)

b (8) 86.468(7) 99.217(5) 100.420(8)

g (8) 64.754(6) 111.514(5) 110.389(8)

Z 2 2 2

V (A3) 2363.0(14) 1352.8(7) 1330.1(11)

dcalcd (g/cm3) 1.671 1.642 1.727

Temperature (K) 293(2) 293(2) 293(2)

Fð000Þ 1196 676 692

m (mm21) 2.112 1.976 3.213

R[I . 2s(I)] R1 0.0657 0.0489 0.0801

wR2 0.1242 0.0867 0.1917

Table 2

Coordination and hydrogen bond lengths (A) for complexes 1, 2 and 3

Coordination bonds in complex 1

Pr(1)–O(6)#1 2.408(8) Pr(2)–O(7) 2.436(8)

Pr(1)–O(9) 2.422(8) Pr(2)–O(4)#2 2.458(8)

Pr(1)–O(1) 2.444(7) Pr(2)–O(8)#2 2.457(9)

Pr(1)–O(2)#1 2.468(8) Pr(2)–O(11)#3 2.509(8)

Pr(1)–O(13) 2.565(7) Pr(2)–O(3) 2.539(9)

Pr(1)–O(5) 2.569(8) Pr(2)–O(12)#3 2.575(8)

Pr(1)–O(6) 2.689(8) Pr(2)–O(4) 2.616(8)

Pr(1)–N(1) 2.698(9) Pr(2)–N(3) 2.666(10)

Pr(1)–N(2) 2.667(9) Pr(2)–N(4) 2.695(10)

Hydrogen bonds in complex 1

O(13w)–H· · ·O(14w)#4 2.939 O(15w)–H· · ·O(5)#1 2.866

O(14w)–H· · ·O(12) 2.886 O(15w)–H· · ·O(11) 2.852

O(16w)–H· · ·O(10)#5 2.821 C(36)–H· · ·O(15w)#6 3.214


Nd(1)–O(3)#1 2.395(5) Nd(1)–O(5) 2.407(5)

Nd(1)–O(4)#2 2.413(5) Nd(1)–O(6)#3 2.521(5)

Nd(1)–O(1) 2.484(5) Nd(1)–N(1) 2.679(6)

Nd(1)–O(2) 2.511(5) Nd(1)–N(2) 2.696(6)


O(7)–H· · ·O(9w)#4 2.620 O(10w)–H· · ·O(8)#6 2.861

O(9w)–H· · ·O(1)#3 2.754 C(17)–H· · ·O(8)#7 3.424

O(9w)–H· · ·O(6)#5 2.794


Er(1)–O(5) 2.259(10) Er(1)–O(6)#3 2.406(10)

Er(1)–O(3)#1 2.294(11) Er(1)–O(2) 2.416(9)

Er(1)–O(4)#2 2.295(10) Er(1)–N(1) 2.563(11)

Er(1)–O(1) 2.386(11) Er(1)–N(2) 2.612(11)


O(7)–H· · ·O(9w)#4 2.615 O(10w)–H· · ·O(8)#6 2.906

O(9w)–H· · ·O(1)#3 2.780 C(17)–H· · ·O(8)#7 3.314

O(9w)–H· · ·O(6)#5 2.811

Symmetry transformations used to generate equivalent atoms in

complex 1: #1 2x þ 1; 2y þ 2; 2z þ 1; #2 2x þ 1; 2y þ 1; 2z; #3 x; y;

z 2 1; #4 x; y þ 1; z; #5 x; y 2 1; z; #6 x 2 1; y; z 2 1: Symmetry

transformations used to generate equivalent atoms in complexes 2 and 3: #1

2x; 2y þ 2; 2z þ 1; #2 x; y 2 1; z; #3 2x; 2y þ 1; 2z þ 1; #4 2x þ 1;

2y þ 2;2z þ 1; #5 2x þ 1;2y þ 1;2z þ 1; #6 2x þ 1;2y þ 2;2z þ 2;

#7 2x þ 1; 2y þ 3; 2z þ 2:

L. Huang et al. / Journal of Molecular Structure 692 (2004) 169–175170

3. Results and discussion

3.1. Structure of [Pr2(pim)3(phen)2(H2O)]n·3n H2O 1

In the asymmetric unit of complex 1, there are two types

of Pr(III) ion environment. As shown in Fig. 1, Pr(1) is

coordinated by two nitrogen atoms from phen ligand and

seven oxygen atoms, of which, one oxygen atom [O(13)]

comes from a water molecule and six from five different

pimelate ligands. Pr(2) is also nine-coordinated and

possesses an N2O7 environment, two nitrogen atoms come

from a chelating phen molecule and seven oxygen atoms

from five pimelate ligands. The Pr–N bond lengths range

from 2.666 to 2.698 A. The average bond length is 2.682 A.

The Pr–O bond lengths range from 2.408 to 2.689 A, of

which the Pr(1)–O(6) (2.689 A) and Pr(2)–O(4) (2.616 A)

are quite long while the other twelve Pr–O bond lengths are

typical. The reason is probably due to the four-membered

ring of chelating–bridging coordination. The average length

of Pr–O bonds is 2.511 A. Three kinds of crystallographi-

cally dependent pimelate ligands exist in complex 1

(Scheme 1): (i) The two carboxylate groups of the pimelate

coordinate to Pr(III) ions in chelating–bridging tridentate

and bridging bidentate modes (Scheme 1a). From C(2) to

C(6), only methylene group of C(5)–C(6) adopts a gauche

conformation [torsion angle: C(4) – C(5) – C(6) – C(7),

69.4(15)8] and the other three pairs of CH2 groups adopt

anti-conformation [torsion angles: C(1)–C(2)–C(3)–C(4),

2175.9(11)8; C(2)–C(3)–C(4)–C(5), 2174.8(12)8; C(3)–

C(4)–C(5)–C(6), 178.0(11)8]. (ii) Similar to (i), the two

carboxylate groups of the pimelate coordinate to Pr(III) ions

also in chelating–bridging tridentate and bridging bidentate

modes (Scheme 1b). But the alkyl chain conformation of

the pimelate is different. In particular, the CH2 group of

C(11)–C(12) adopts an unfavorable eclipsed conformation

[torsion angle: C(10)–C(11)–C(12)–C(13), 2113(2)8]

Fig. 1. The asymmetric unit of [Pr2(pim)3(phen)2(H2O)]n·3n H2O (1) showing 50% thermal ellipsoids. All hydrogen atoms are omitted for clarity.

Scheme 1. Coordination modes of pimelate groups in complexes 1 and 2, showing different alkyl chains conformation of pimelate [a, b, c and d (gauche-form);

e (anti-form)].

L. Huang et al. / Journal of Molecular Structure 692 (2004) 169–175 171

and the other three pairs of CH2 groups are anti-

conformation [torsion angles: C(8)–C(9)–C(10)–C(11),

178.4(13)8; C(9) – C(10) – C(11) – C(12), 2179.8(15)8;

C(11)–C(12)–C(13)–C(14), 168.4(19)8]. So, it is easy to

understand that C(11), C(12) and C(13) have large ellipsoids

duo to the eclipsed conformation. (iii) One carboxylate

group of the pimelate ligand coordinates to Pr(III) ion in

chelating bidentate mode and the other coordinates to Pr(III)

ion in monodentate mode (Scheme 1c). In the pimelate alkyl

chain, two pairs of CH2 groups adopt gauche conformation

[torsion angles: C(15)–C(16)–C(17)–C(18), 68.8(15)8;

C(18)–C(19)–C(20)–C(21), 63.7(15)8] and the other two

adopt anti-conformation [torsion angles: C(16)–C(17)–

C(18)–C(19), 178.9(11)8; C(17)–C(18)–C(19)–C(20),

172.2(11)8]. Pr(III) ions are bridged by pimelate ligands

into 2D layer structure (Fig. 2). There are two types of

crystallographically dependent phen ligands in complex 1.

They coordinate to Pr(III) ions in chelating mode and

protrude from the polymeric layer in two different

directions. One type of p–p interaction is observed

between two adjacent layers (Scheme 2a). The average

distance between two parallel phen ligands from two

adjacent layers is 3.55 A. Lattice water molecules are

stabled in the crystal by hydrogen bondings between

Fig. 2. Projection down the a-axis showing 2D layer structure connected by three types of pimelate ligands (All H atoms and C atoms of phen ligands are

omitted for clarity).

Scheme 2. Packing of phen ligands in complexes 1 and 2.


coordinated water and lattice water, carboxylate oxygen and

lattice water, and C–H of phen and lattice water (Table 2).

A triple hydrogen bond is formed by O(15w) from lattice

water, O(15w) – H· · ·O(5)#1, O(15w) – H· · ·O(11) and

C(36)#7 –H· · ·O(15w) (#1: 2x þ 1;2y þ 2;2z þ 1; #7:

x þ 1; y; z þ 1). The triple hydrogen bonding and p–p

stacking between polymeric layers result in 3D supramo-

lecular structure.

3.2. Structure of [Ln(Hpim)(pim)(phen)]n·1.5n H2O

(Ln ¼ Nd, 2; Er, 3)

Single-crystal X-ray diffraction studies reveal that

complexes 2 and 3 are isostructural. The asymmetric unit

of 2 is shown in Fig. 3. There is one type of Nd(III) ion

environment in the asymmetric unit of 2. As shown in Fig. 3,

Nd(1) is eight-coordinated and surrounded by two nitrogen

atoms from a phen molecule and six carboxylate oxygen

atoms, four of which come from pim ligands and two from

Hpim ligands. The Nd–O bond distances range from

2.395(5) to 2.521(5) A. The average distance is 2.455 A.

The Nd–N bond distances are 2.679(6) and 2.696(6) A,

respectively. The pim ligands coordinate to four Nd(III)

ions in chelating bidentate and bridging bidentate modes

(Scheme 1d). From C(2) to C(6), only methylene group of

C(2)–C(3) adopts a gauche conformation [torsion angle:

C(1)–C(2)–C(3)–C(4), 271.6(8)8] and the other CH2

groups adopt anti-conformation [torsion angles: C(2)–

C(3) – C(4) – C(5), 169.5(6)8; C(3) – C(4) – C(5) – C(6),

175.0(7)8; C(4)–C(5)–C(6)–C(7) 166.5(6)8]. Nd(III) ions

are connected by pim ligands into 1D chain structure. In the

1D structure, all Nd(III) ions are coplanar. The nearest

Nd· · ·Nd distance is 4.0503(11) A, indicating the lack of

direct metal–metal interaction. The carboxylate group of

Hpim ligand coordinates to two Nd(III) ions in bridging

bidentate mode and the undissociated carboxylic group of

Hpim ligand protrudes from polymeric chain forming

hydrogen bonds to lattice water molecules and C–H of

phen from adjacent chain (Scheme 1e). The alkyl chain

conformation of Hpim is anti-form [torsion angles: C(8)–

C(9)–C(10)–C(11), 179.4(7)8; C(9)–C(10)–C(11)–C(12),

2175.8(7)8; C(10) – C(11) – C(12) – C(13), 171.6(8)8;

C(11)–C(12)–C(13)–C(14), 2177.4(8)8;]. Phen ligands

coordinate to Nd(III) ions in chelating mode and locate at

both sides of the chain. p–p interactions exist between

phen ligands from adjacent chains with the average distance

of 3.43 A (Scheme 2b). There are two kinds of crystal-

lographically dependent lattice water molecules in complex

2, one of them forms a triple hydrogen bond shown as dotted

line in Fig. 4 and the other due to its partial occupancy forms

a weak hydrogen bond to oxygen atom of carbonyl group

from Hpim ligand. The relevant hydrogen bond lengths are

listed in Table 2. As shown in Fig. 4, 2D network parallel to

b–c plane is formed via p–p interactions between chains.

Then 2D networks are interconnected into 3D supramole-

cular structure via three hydrogen bond bridging centers and

C–H· · ·O hydrogen bonds between chains.

3.3. IR spectra

The IR spectrum of complex 1 shows characteristic

bands of the carboxylate groups in the usual region at

1578(vs) and 1560(vs) cm21 for asymmetric stretching and

at 1421(vs) cm21 for symmetric stretching (Shoulders not

listed) [12]. In both spectra of complexes 2 and 3, the

characteristic bands of the carboxylate groups occur within

the range 1542–1610 cm21 for asymmetric stretching and

the range 1407–1439 cm21 for symmetric stretching.

Comparing the spectra of three complexes, C–H stretching

vibrations appear above 3000 cm21 [13,14] and character-

istic C–H out-of-plane bending vibrations are seen at about

731 and 850 cm21, indicating the presence of phen ligands

[13]. The O–H (from the coordinated and lattice water

molecules or the hydroxyl of Hpim ligand) stretching bands

Fig. 3. The asymmetric unit of [Nd(Hpim)(pim)(phen)]n·1.5n H2O 2 showing 50% thermal ellipsoids. The hydrogen atoms attached to C atoms are omitted for

clarity.


centered at 3400 cm21 are broadened by hydrogen bonding

[14]. Asymmetric and symmetric stretching of CH2 from

pimelate occurs at about 2900 cm21 [7,8,13]. In comparison

of the spectrum of complex 1 with those of complexes

2 and 3, characteristic bands of CvO double bond are

observed at 1718(s) cm21 for 2 and 1716(s) cm21 for 3,

indicating the occurrence of Hpim ligand [14,15], which is in

accordance with the results of single crystal X-ray analysis.

4. Conclusion

First examples of lanthanide coordination polymers

constructed by H2pim and phen, [Pr2(pim)3(phen)2

(H2O)]n·3n H2O 1 and [Ln(Hpim)(pim)(phen)]n·1.5n H2O

(Ln ¼ Nd, 2; Er, 3) have been obtained by hydrothermal

synthesis and characterized by single crystal X-ray analysis.

Both the average Ln–O bond distance and coordination

number of the Ln(III) ions show lanthanide contraction in

the series. The Pr(III) ions in 1 are bridged by pim ligands

forming a layer structure, while chains in 2 and 3 are formed

by the coordination of pim and Hpim to Ln(III) ions and are

further assembled via p–p stacking and a variety of

hydrogen bonds to give a 3D network. In addition, IR

spectra of the complexes 1, 2 and 3 support the results of the

X-ray diffraction analysis.

5. Supporting information available

The crystallographic data have been deposited at Cam-

bridge Crystallographic Data Centre, CCDC Nos 224870

for 1, 224871 for 2 and 224872 for 3. Copies of this

information may be obtained free of charge from the

director, CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK

(E-mail: [email protected]; fax: þ44-1223-336033;

http://www.ccdc.cam.ac.uk).

References

[1] P.J. Hagrman, D. Hagrman, J. Zubieta, Angew. Chem. Int. Ed. 38

(1999) 2638.

[2] B. Moulton, M.J. Zaworotko, Chem. Rev. 101 (2001) 1629.

[3] M. Eddaoudi, D.B. Moler, H. Li, B. Chen, T.M. Reineke, M.

O’Keeffe, O.M. Yaghi, Acc. Chem. Res. 34 (2001) 319.

[4] (a) R. Cao, D.F. Sun, Y.C. Liang, M.C. Hong, K. Tatsumi, Q. Shi,

Inorg. Chem. 41 (2002) 2087.

(b) D.Q. Chu, J.Q. Xu, L.M. Duan, T.G. Wang, A.Q. Tang, L. Ye, Eur.

J. Inorg. Chem. (2001) 1135.

[5] (a) S.S.-Y. Chui, S.M.-F. Lo, J.P.H. Charmant, A.G. Orpen, I.D.

Williams, Science 283 (1999) 1148.

(b) O.M. Yaghi, H. Li, T.L. Groy, J. Am. Chem. Soc. 118 (1996)

9096.

(c) H.J. Choi, M.P. Suh, J. Am. Chem. Soc. 120 (1998) 10622.

(d) J.-C. Dai, X.-T. Wu, Z.-Y. Fu, C.-P. Cui, S.-M. Hu, W.-X. Du,

L.-M. Wu, H.-H. Zhang, R.-Q. Sun, Inorg. Chem. 41 (2002) 1391.

(e) O.M. Yaghi, G. Li, H. Li, Nature 378 (1995) 703.

Fig. 4. Packing of the chains showing the 3D network via hydrogen bonding and p–p stacking in 2 viewed down the b-axis.


mailto:[email protected]

http://www.ccdc.cam.ac.uk

[6] (a) Y. Wan, L. Zhang, L. Jin, S. Gao, S. Lu, Inorg. Chem. 42 (2003)

4985.

(b) H. Li, M. Eddaoudi, M. O’Keeffe, O.M. Yaghi, Nature 402 (1999)

276.

(c) S.M.-F. Lo, S.S.-Y. Chui, L.-Y. Shek, Z. Lin, X.X. Zhang, G.-H.

Wen, I.D. Williams, J. Am. Chem. Soc. 122 (2000) 6293.

(d)M.Eddaoudi,H.Li,O.M.Yaghi,J.Am.Chem.Soc.122(2000)1391.

(e) L. Pan, N.W. Zheng, Y.G. Wu, S. Han, R.Y. Yang, X.Y. Huang, J.

Li, Inorg. Chem. 40 (2001) 828.

(f) L. Deakin, A.M. Arif, J.S. Miller, Inorg. Chem. 38 (1999) 5072.

[7] (a) E.W. Lee, Y.J. Kim, D.Y. Jung, Inorg. Chem. 41 (2002) 501.

(b) Y.J. Kim, D.Y. Jung, Inorg. Chem. 39 (2000) 1470.

(c) M. Kurmoo, J. Mater. Chem. 9 (1999) 2595.

(d) M. McCann, M.T. Casey, M. Devereux, M. Curran, V. McKee,

Polyhedron 16 (16) (1997) 2741.

(e) Y.J. Kim, E.W. Lee, D.Y. Jung, Chem. Mater. 13 (2001) 2684.

(f) C. Livage, C. Egger, G. Ferey, Chem. Mater. 13 (2001) 410.

(g) C. Livage, C. Egger, M. Nogues, G. Ferey, J. Mater. Chem. 8

(1998) 2743.

(h) T.A. Bowden, H.L. Milton, A.M.Z. Slawin, P. Lightfoot, Dalton

(2003) 936.

[8] V. Kiritsis, A. Michaelides, S. Skoulika, S. Golhen, C. Ouahab, Inorg.

Chem. 37 (1998) 3407.

[9] L.P. Zhang, Y.H. Wan, L.P. Jin, J. Mol. Struct. 646 (2003) 169.

[10] A. Dimos, D. Tsaousis, A. Michaelides, S. Skoulika, S. Golhen, L.

Ouahab, C. Didierjean, A. Aubry, Chem. Mater. 14 (2002) 2616.

[11] G.M. Sheldrick, SHELXS 97 and SHELXL 97, University of Gottingen,

Germany, 1997.

[12] G.B. Deacon, J. Phillips, Coord. Chem. Rev. 33 (1980) 227.

[13] M. Geraghty, M. McCann, M.T. Casey, M. Curran, M. Devereux, V.

McKee, J. McCrea, Inorg. Chim. Acta 277 (1998) 257.

[14] F.W. Fifield, D. Kealey, in: Principles and Practice of Analytical

Chemistry, fifth ed., Blackwell Science, Oxford, 2000, pp. 378–393.

[15] L.P. Zhang, Y.H. Wan, L.P. Jin, Polyhedron 22 (2003) 981.


hydrothermal synthesis and structural characterization of new lanthanide coordination polymers with...

Documents