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phate leading to a trimeric-capped type structure with nominal C 3v symmetry. Interaction of solid TiO(SO 4 ) with [γ-SiW 10 O 36 ] 8− in an aqueous acidic medium resulted in a novel, tetrameric polyoxometalate [β-Ti 2 SiW 10 O 39 ] 4 ] 24− (11).It has been characterized by multinuclear NMR spectroscopy, FTIR spectroscopy and elemental analysis. Single-crystal X-ray analysis of the compound showed that it crystallizes in monoclinic system, space group P 2 1 /n, a = 12.5188(13) Å, b = 18.864(2) Å, c = 41.075(4) Å, β = 97.450(2) ◦ Z = 2. The polyanion is composed of four β-Ti 2 SiW 10 O 39 Keggin fragments that are linked via Ti-O-Ti bridges leading to a cyclic assembly. The solid-state structure of K 24 [(β-Ti 2 SiW 10 O 39 ) 4 ]·50H 2 O shows face-by-face self assembled polyanions (K-11) along the crystallographic ‘a’ axis, which leads to a nanotube-like arrangement. The cadmium(II)-substituted tungstoarsenate [Cd 4 Cl 2 (B-α-AsW 9 O 34 ) 2 ] 12− (12) has been synthesized and characterized in the solid state by XRD, FTIR spectroscopy, elemental analysis and 183 W and 111 Cd NMR spectroscopy. Single crystal X-ray analysis of Cs 4 K 3 Na 5 [Cd 4 Cl 2 (B-α-AsW 9 O 34 ) 2 ]·20H 2 O (CsKNa-12), shows that it crystallizes in the monoclinic system, space group P 2 1 /n, with a = 13.1402(12) Å, b = 19.0642(17) Å, c = 17.5666(15) Å, β = 90.274(2) ◦ and Z = 2. Polyanion (9) consists of two lacunary [B-α-AsW 9 O 34 ] 10− Keggin moieties linked via a rhomb like (Cd 4 O 14 Cl 2 ) cluster leading to a sandwich-type structure. Interestingly, the two external Cd atoms each have a terminal Cl ligand, but the derivative have terminal water ligands, [Cd 4 (H 2 O) 2 (B-α-AsW 9 O 34 ) 2 ] 10− (13), which has been proved by 183 W and 111 Cd NMR spectroscopy. The indium(III)-substituted polyanions [In 3 Cl 2 (B-α-PW 9 O 34 ) 2 ] 11− (14), [In 3 Cl 2 (P 2 W 15 O 56 ) 2 ] 17− (15), [In 4 (H 2 O) 10 ( β-AsW 9 O 32 OH) 2 ] 4− (16) and [In 4 (H 2 O) 10 (β-SbW 9 O 33 ) 2 ] 6− (17) have been synthesized and characterized in the solid state by FTIR spectroscopy and elemental analysis and 183 W-NMR. Single-crystal X-ray analysis showed that D,L- (NH 4 ) 11 [In 3 Cl 2 (B-α-PW 9 O 34 ) 2 ]·16H 2 O (NH4-14) showed that it crystallizes in the monoclinic system, space group P 2 1 /n, with a = 17.5090(10) Å, b = 12.7361(7) Å, c = 18.7955(11) Å, β = 107.3030(10) ◦ , and Z = 2; D,L- (NH 4 ) 9 Na 8 [In 3 Cl 2 (P 2 W 15 O 56 ) 2 ]·39H 2 O (NH4Na-15) crystallizes in the triclinic system, space group P ¯1, with a = 13.0643(5) Å, b = 14.8901(6) Å, c = 19.8603(8) Å, α = 92.2920(10) ◦ , β = 90.8680(10) ◦ , γ = 100.5630(10) ◦ , and Z = 1; RbNa 3 [In 4 (H 2 O) 10 (βiv
AsW 9 O 32 OH) 2 ]·36H 2 O (RbNa-16) crystallizes in the triclinic system, space group P ¯1, with a = 12.8142(5) Å, b = 12.8672(5) Å, c = 16.1794(7) Å, α = 91.1370(10) ◦ , β = 105.9450(10) ◦ , γ = 104.0980(10) ◦ and Z = 1; K 4 Na 2 [In 4 (H 2 O) 10 (β-SbW 9 O 33 ) 2 ]·30H 2 O (KNa-17) crystallizes also in the triclinic system, space group P ¯1, with a = 12.2306(9) Å, b = 12.7622(10) Å, c = 16.1639(12) Å, α = 73.9890(10) ◦ , β = 76.5550(10) ◦ , γ = 86.2130(10) ◦ and Z = 1. Synthesis of polyanions 14-17 have been accomplished by reaction of In 3+ ions with the lacunary precursors [B-α-PW 9 O 34 ] 9− , [P 2 W 15 O 56 ] 12− and [α-XW 9 O 33 ] 9− (X = As III , Sb III ), respectively, in aqueous, acidic medium. The chiral polyanions 14 and 15 are composed of three In(III) ions connected to two (B-α-PW 9 O 34 ) and (P 2 W 15 O 56 ) fragments, respectively. Only one of the inner sites of the central rhombus is occupied by an indium atom and the two outer indium atoms contain a terminal Cl ligand. The structural stability of the polyanions 14-17 in solution were studied by 31 P and 183 W NMR. v
Page 1 and 2: Hybrid Organic-Inorganic Polyoxomet
Page 3 and 4: Abstract Polyoxometalates (POMs) ar
Page 5: the cubic system (space group I m¯
Page 9 and 10: Paris-Sud, Orsay Cedex, France) for
Page 11 and 12: 2.2.9 Synthesis of K 12 [H 2 P 2 W
Page 13 and 14: Bibliography . . . . . . . . . . .
Page 15 and 16: 3.5 Left: combined polyhedral and b
Page 17 and 18: 3.33 Combined polyhedron and ball/s
Page 19 and 20: List of Tables 1.1 Selected M-M dis
Page 21 and 22: MO 6 octahedra surrounding a centra
Page 23 and 24: 1.1.1 The clathrate-like structure
Page 25 and 26: 7(MoO 4 ) 2− + 8H + → [Mo 7 O 2
Page 27 and 28: Fig. 1.4: Combined polyhedral/ball
Page 29 and 30: This planar structure was originall
Page 31 and 32: [X 2 M 18 O 62 ] 6− , the D 3h We
Page 33 and 34: [P 2 W 19 O 68 (HO)] 14− , [P 2 W
Page 35 and 36: Fig. 1.11: Monomeric (left) and dim
Page 37 and 38: Chapter 2 Experimental 2.0.1 Reagen
Page 39 and 40: 2.2 Preparation of starting materia
Page 41 and 42: as Cs 6 [P 2 W 5 O 23 ]·7H 2 O by
Page 43 and 44: was adjusted between 5-6 by additio
Page 45 and 46: Chapter 3 Results 3.1 The hybrid or
Page 47 and 48: Fig. 3.2: FTIR spectra of compound
Page 49 and 50: Fig. 3.3: W 183 NMR spectra of (CsN
Page 51 and 52: Fig. 3.5: Left: combined polyhedral
Page 53 and 54: formed upon crystallization and bot
Page 55 and 56: X-ray Crystallography A crystal of
Page 57 and 58:
the presence of the four (CH 3 ) 2
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Fig. 3.10: Cyclic voltammogram of 2
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as a function of electrolyte compos
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was observed that could be traced t
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electrochemical set-up was an EG &
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Fig. 3.14: The central core of Sn(C
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of these fragments [88, 90]. For co
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diffractometer using Mo K α radiat
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Fig. 3.18: Side view of [{Sn(CH 3 )
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host−guest systems with large cav
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X-ray Crystallography Single crysta
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3.5.2 Results and discussions Polya
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Fig. 3.26: Ball and stick represent
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can distinguish between different m
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Fig. 3.28: STM pictures of {Sn(CH 3
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Fig. 3.31: Size distribution by int
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3.6 The bis-phenyltin substituted,
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Table 3.7: Crystal Data and Structu
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tral belt in-between the two tin at
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Fig. 3.35: 183 W NMR spectra of com
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whereas they are five-coordinated (
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investigated by scanning tunneling
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3.8 The di-titanium substituted, lo
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Fig. 3.37: Ball/stick (left), polyh
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[As 2 W 19 O 67 (H 2 O)] 14− , [A
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3.9 The cyclic trimeric-titanium su
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Table 3.9: Crystal Data and Structu
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Fig. 3.40: FTIR spectra of compound
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Fig. 3.42: Side-view of compound 11
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11 by 183 W-NMR (at 16.66 MHz on a
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3.11 Structure and solution propert
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472(w), 444(w) cm −1 . This proce
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MHz in 10 mm tubes and the 111 Cd N
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Fig. 3.47: 111 Cd NMR spectra of [C
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in aqueous solution, so that the nu
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of cadmium ions in 12 and 13 and it
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doubtedly 183 W-NMR, but the parama
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K): (relative intensities in parent
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Fig. 3.49: Combined polyhedral/ball
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Fig. 3.50: 183 W NMR spectrum of [I
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(17) are isostructural. They consis
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Fig. 3.53: 183 W NMR spectrum of [I
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3.12.4 Conclusion We have synthesiz
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[37] D. Gatteschi, O. Kahn, J. Mill
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94:226403, 2005. [123] R. J. Hamers
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[206] I. Loose, E. Droste, M. Bösi
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NMR Spectra Fig. 3.54: 13 C NMR spe
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Fig. 3.56: 31 P NMR spectrum of pol
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Fig. 3.58: 13 C NMR spectrum of pol
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Fig. 3.60: 1 H NMR spectrum of poly
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Fig. 3.62: 119 Sn NMR spectrum of p
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Fig. 3.66: 1 H NMR spectrum of poly
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Fig. 3.70: 13 C NMR spectrum of pol
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were applied and an absorption corr
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Fig. 3.75: Size distribution by num
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Table 3.16: Crystal Data and Struct
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Fig. 3.80: FTIR spectra of compound
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FIRASAT HUSSAIN International Unive
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Publications 1. Observation of a Ha
Page 175 and 176:
PAPERS IN CONFERENCE/ SYMPOSIA / WO
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