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Table 3.1: Crystal Data and Structure Refinement for compounds CsNa-1 and CsNa-2 formula AsC 6 CsH 36 Na 4 O 43 Sn 3 W 9 (1) C 6 CsH 36 Na 4 O 43 SbSn 3 W 9 (2) fw (g/mol) 3107 3153.8 crystal color colorless colorless crystal system orthorhombic orthorhombic crystal size (mm 3 ) 0.10 × 0.06 × 0.02 0.11 × 0.06 × 0.04 space group (No.) P na2 1 (33) P na2 1 (33) unit cell dim. a (Å) 26.118(2) 26.118(2) b (Å) 16.064(1) 16.064(1) c (Å) 13.776(1) 13.776(1) vol (Å 3 ) 5779.4(7) 5779.4(7) Z 1 1 dcalc (Mg m −3 ) 3.561 3.672 abs. coeff. (mm −1 ) 20.548 20.595 Reflections (unique) 14373 14370 Reflections (obs.) 11413 12214 a R (F o) 0.068 0.052 b R w(F o) 0.1401 0.1078 diff. peak (eÅ 3 ) 5.248 2.985 diff. hole (eÅ 3 ) -5.107 -3.762 R = ∑ ||F o |-|F c ||/ ∑ |F o |. b R w = [ ∑ w(F 2 o-F 2 c) 2 / ∑ w(F 2 o) 2 ] 1/2 (CsNa 4 [{Sn(CH 3 ) 2 } 3 O(H 2 O) 4 (β-AsW 9 O 33 )]·5H 2 O) 183 ∞ W: (relative intensities in parenthesis) -130.5(2), -135.2(1), -138.1(2), -142.5(2), -146.2(2) ppm; 119 Sn: -175.9(1), -200.0(2) ppm; 13 C: 8.5 ppm; 1 H: 0.7 ppm. NMR (D 2 O, 293 K) for (CsNa 4 [{Sn(CH 3 ) 2 } 3 O(H 2 O) 4 (β- SbW 9 O 33 )]·5H 2 O) : 183 W: (relative intensities in parenthesis) -108.1(2), -117.4(1), -120.1(2), -127.1(2), -134.7(2) ppm; 119 Sn: -164.6(1), -205.2(2) ppm; 13 C: 8.7 ppm; 1 H: 0.7 ppm. All NMR spectra were recorded with freshly synthesized, concentrated solutions of CsNa-1 and CsNa-2 on a JEOL Eclipse 400 instrument. The 183 W-NMR measurements were performed at 16.656 MHz in 10 mm tubes and the 119 Sn, 13 C, and 1 H spectra were recorded in 5 mm tubes at 149.081, 100.525 and 399.782 MHz, respectively. The chemical shifts for unbound dimethyltin dichloride at pH 3 are at -243.7 ppm ( 119 Sn), 12.2 ppm ( 13 C) and 0.84 ppm ( 1 H), respectively. 29
Fig. 3.3: W 183 NMR spectra of (CsNa 4 [{Sn(CH 3 ) 2 } 3 O(H 2 O) 4 ( β-XW 9 O 33 )]·5H 2 O) ([X = As (top)CsNa- 1, Sb (bottom)CsNa-2] 3.1.2 Results and discussion The novel and isostructural polyoxoanion-based 2-D materials (CsNa 4 [Sn(CH 3 ) 2 } 3 O(H 2 O) 4 (β-XW 9 O 33 )]·5H 2 O) (X = As, CsNa-1; Sb, CsNa-2), see Figures 3.5. The structure of CsNa-1 and CsNa-2 is best described as a polymeric network composed of monopolyanionic building blocks ({Sn(CH 3 ) 2 (H 2 O) 2 } 3 (β-XW 9 O 33 )) (X = As, Sb) that are linked via Sn-O-(W’) bridges. This leads to a 2-D surface which is not planar, but could perhaps be described as a shelf with a zig-zag backbone where the individual levels are decorated by methyl groups. Clearly, the solid state structure is governed by the organic functionalities. Compounds CsNa-1 and CsNa-2 are isostructural, which means that the different sizes of the As and Sb heteroatoms with their associated lone pairs have no significant effect on the solid state structures. The three organo-tin groups attached to each monomeric unit of CsNa-1 and CsNa-2 contain tin centers that are octahedrally coordinated by two oxo groups, two methyl groups and two water molecules, respectively. Furthermore the two methyl groups on each tin atom are positioned trans to each other. However, only two organotin groups are structurally equivalent and different from the third. The molecular formulae and charges of CsNa-1 and CsNa-2 are supported by bond valence 30
Page 1 and 2: Hybrid Organic-Inorganic Polyoxomet
Page 3 and 4: Abstract Polyoxometalates (POMs) ar
Page 5 and 6: the cubic system (space group I m¯
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: Fig. 3.2: FTIR spectra of compound
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
Page 59 and 60: Fig. 3.10: Cyclic voltammogram of 2
Page 61 and 62: as a function of electrolyte compos
Page 63 and 64: was observed that could be traced t
Page 65 and 66: electrochemical set-up was an EG &
Page 67 and 68: Fig. 3.14: The central core of Sn(C
Page 69 and 70: of these fragments [88, 90]. For co
Page 71 and 72: diffractometer using Mo K α radiat
Page 73 and 74: Fig. 3.18: Side view of [{Sn(CH 3 )
Page 75 and 76: host−guest systems with large cav
Page 77 and 78: X-ray Crystallography Single crysta
Page 79 and 80: 3.5.2 Results and discussions Polya
Page 81 and 82: Fig. 3.26: Ball and stick represent
Page 83 and 84: can distinguish between different m
Page 85 and 86: Fig. 3.28: STM pictures of {Sn(CH 3
Page 87 and 88: Fig. 3.31: Size distribution by int
Page 89 and 90: 3.6 The bis-phenyltin substituted,
Page 91 and 92: Table 3.7: Crystal Data and Structu
Page 93 and 94: tral belt in-between the two tin at
Page 95 and 96: Fig. 3.35: 183 W NMR spectra of com
Page 97 and 98: whereas they are five-coordinated (
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investigated by scanning tunneling
Page 101 and 102:
3.8 The di-titanium substituted, lo
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Fig. 3.37: Ball/stick (left), polyh
Page 105 and 106:
[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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