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Reacting (CH 3 ) 2 SnCl 2 with the superlacunary polyanion [H 2 P 4 W 24 O 94 ] 22− resulted in a dimeric hybrid organic-inorganic polyanion, [{Sn(CH 3 ) 2 } 4 (H 2 P 4 W 24 O 94 ) 2 ] 36− (3).It has been characterized by multinuclear NMR spectroscopy, FTIR spectroscopy and elemental analysis. Single-crystal X-ray analysis of K 17 Li 19 [{Sn(CH 3 ) 2 } 4 (H 2 P 4 W 24 O 94 ) 2 ]·51H 2 O showed that it crystallizes in the tetragonal system, space group P 4 2 /nmc, a = b = 21.5112(17) Å, c = 27.171(3) Å, Z = 2. Polyanion 3 is composed of two (H 2 P 4 W 24 O 94 ) fragments that are linked by four equivalent diorganotin groups. The unprecedented assembly 3 has D 2d symmetry and contains a hydrophobic pocket at its center. The trimeric, hybrid organic-inorganic tungstophophate(V) [{Sn(CH 3 ) 2 (OH)} 3 (Sn(CH 3 ) 2 ) 3 {A-PW 9 O 34 } 3 ] 18− (4) has been synthesized in acidic medium. It has been characterized by FTIR spectroscopy, elemental analysis and cyclic voltametry. Single-crystal X-ray analysis of the compound showed that it crystallizes in rhombohedral system, space group R 3m, a = b = 29.7445(7) Å, c = 15.5915(7) Å, Z = 3. The polyanion is composed of three (A-α-PW 9 O 34 ) fragments that are linked by six dimethyltin groups, where the outer three ones are connected by µ 2 − OH bridges leading to a cyclic core which act as a cap leading to a bowl type structure. This arrangement results in a cyclic, trimeric, unprecedented polyanion assembly with C 3v symmetry. The tetrameric, hybrid organic-inorganic tungstoarsenate(III) [{Sn(CH 3 ) 2 (H 2 O)} 2 {Sn(CH 3 ) 2 }As 3 (α-AsW 9 O 33 ) 4 ] 12− (5) 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 the monoclinic system, space group P 21/c, with a = 22.612(2) Å, b = 19.954(2) Å, c = 41.099(4) Å, Z = 4. Polyanion 5 is composed of four (B-α-AsW 9 O 33 ) fragments that are linked by three dimethyltin groups and three As(III) atoms resulting in an unprecedented, chiral polyoxoanion assembly with C 1 symmetry. Interaction of (CH 3 ) 2 SnCl 2 with Na 9 [A-XW 9 O 34 ] (X = P V , As V ) in aqueous acidic medium resulted in the dodecameric, ball-shaped anions [{Sn(CH 3 ) 2 (H 2 O)} 24 {Sn(CH 3 ) 2 } 12 (A-XW 9 O 34 ) 12 ] 36− (X = P V , As V ) (6-7). They has been characterized by multinuclear NMR spectroscopy, FTIR spectroscopy, scanning tunneling microscopy and elemental analysis. Both compounds crystallize as mixed cesium-sodium salts and are isomorphous. Single crystal Single-crystal X-ray analysis of the compound showed that it crystallizes in ii
the cubic system (space group I m¯3 with a = b = c = 32.7441(4) Å, Z = 2 . The spherical structure of the polyanion is spectacular in terms of geometry and size (diameter of 30 Å) and is unprecedented in polyoxotungstate chemistry. This supermolecular assembly is composed of 12 trilacunary [A-XW 9 O 34 ] 9− (X= As V , P V ) Keggin fragments which are linked by 36 dimethyltin groups [12 inner (CH 3 ) 2 Sn 2+ and 24 outer (CH 3 ) 2 (H 2 O)Sn 2+ groups] resulting in a polyanion with T h symmetry. The polyanion contains 1000 atoms with a molar mass of around 33000 gmol −1 . The bis-phenyltin substituted lone pair containing tungstoarsenate [(C 6 H 5 Sn) 2 As 2 W 19 O 67 (H 2 O)] 8− (8) has been synthesized and characterized by multinuclear NMR, FTIR spectroscopy and elemental analysis. Single-crystal X-ray analysis of (NH 4 ) 7 Na[(C 6 H 5 Sn) 2 As 2 W 19 O 67 (H 2 O)]·17.5H 2 O showed that it crystallizes in the monoclinic system, space group P 2 1 /c, with, a = 18.3127(17) Å, b = 24.403(2) Å, c = 22.965(2) Å, β= 106.223(2) ◦ , and Z = 4. Polyanion 8 consists of two B-α-(As III W 9 O 33 ) Keggin moieties linked via WO(H 2 O) fragment and two (SnC 6 H 5 ) 3+ groups leading to a sandwich-type structure with nominal C 2v symmetry. The titanium(IV), disubstituted lone pair containing tungstoarsenate [(TiOH) 2 WO(H 2 O)As 2 W 19 O 67 ] 8− (9) has been synthesized and characterized by FTIR spectroscopy and elemental analysis. Single-crystal X-ray analysis was carried out on Cs 8 [(TiOH) 2 WO(H 2 O)As 2 W 19 O 67 ]·10.5H 2 O which crystallizes in the monoclinic system, space group P 2 1 /m , with a = 12.7764(19)Å, b = 19.425(3) Å, c = 18.149(3) Å, β=110.23(3) ◦ , and Z = 2. Polyanion (9) consists of two B-α-(As III W 9 O 33 ) Keggin moieties linked via one [WO(H 2 O)] 4+ fragment and two Ti 4+ ions leading to a sandwich-type structure with nominal C 2v symmetry. Interaction of solid TiO(SO 4 ) with K 14 [P 2 W 19 O 69 (OH 2 )] in an aqueous acidic medium resulted in a novel, trimeric polyoxometalate . The compound has been characterized by FTIR spectroscopy and elemental analysis. Single-crystal X-ray analysis of the compound showed that it crystallizes in rhombohedral system, space group R 3m, a = b = 29.7444(7) Å, c = 13.6254(9) Å, Z = 3. The polyanion (10) is composed of three α- Ti 3 PW 9 O 34 Keggin fragments that are linked via Ti-O-Ti bridges leading to a trimeric assembly. Interestingly, one of the titanium from each fragment is connected to the phosiii
Page 1 and 2: Hybrid Organic-Inorganic Polyoxomet
Page 3: Abstract Polyoxometalates (POMs) ar
Page 7 and 8: AsW 9 O 32 OH) 2 ]·36H 2 O (RbNa-1
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
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X-ray Crystallography A crystal of
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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
Page 173 and 174:
Publications 1. Observation of a Ha
Page 175 and 176:
PAPERS IN CONFERENCE/ SYMPOSIA / WO
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