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2.2.4 Synthesis of A & B Na 8 [HAsW 9 O 34 ]·11H 2 O (A & B-Type AsW 9 O 34 ) 30 g of Na 2 WO 4·2H 2 O and 2.3 g of As 2 O 5 were dissolved in 40 mL of distilled water with stirring. Glacial CH 3 COOH was added drop wise until the pH changed to 8.1 or 8.3 the solution turned milky on addition of CH 3 COOH but after stirring for a period of 30 min a heavy white precipitate was formed. The precipitate was filtered on a frit and air dried. The product obtained is A-AsW 9 O 34 . If the above product is kept in the oven for a period of 2hrs at ∼140 ◦ C it isomerizes to give B-AsW 9 O 34 . These synthesis was done with slight modification to the published method. They were characterized by FTIR spectroscopy and compared to the A & B reported spectrum [72]. 2.2.5 Synthesis of A-Na 9 [PW 9 O 34 ]·7H 2 O 120 g (0.36 mol) of Na 2 WO 4·2H 2 O were dissolved in 150 g of distilled water. H 3 PO 4 (85%) was added dropwise with stirring. After the completion of addition, the pH of the solution was measured to be 8.9. Glacial CH 3 COOH was added dropwise with vigorous stirring. Large quantities of white precipitate were formed during the addition. The final pH of the solution was 7.8. The solution was stirred at least for an hour and the precipitate was collected on a medium frit. Heating of the crude product at ∼120 ◦ C induces a solid state isomerization from A-type to B-type. These compounds were characterized by FTIR spectroscopy and 31 P-NMR spectroscopy and compared to the FTIR reported spectrum [73]. 2.2.6 Synthesis of Cs 6 [P 2 W 5 O 23 ]·H 2 O 60 g ( 0.24 mol) of H 2 WO 4 was slurried with 200 g of water. Approximately 110 mL of a 50% aqueous CsOH solution was added drop wise with vigorous stirring. The turbid solution was filtered through a cake of 10 g celite and to the clear colorless filtrate H 3 PO 4 (85%) was added drop wise while stirring to adjust the pH to 7.0. The solution was again stirred for an hour and filtered again. The filtrate was cooled to ∼0 ◦ C in refrigerator for 24 hours and the white crystalline solid was formed which was identified 21
as Cs 6 [P 2 W 5 O 23 ]·7H 2 O by FTIR spectroscopy [73]. 2.2.7 Synthesis of Cs 7 [PW 10 O 36 ]·H 2 O 75 g of Cs 6 [P 2 W 5 O 23 ]·H 2 O synthesized by the above procedure was dissolved in 150 g of water and the resulting was refluxed for 24 hour. The solution was filtered hot through a medium frit to obtain the crude product Cs 7 [PW 10 O 36 ]·H 2 O. The filtrate was cooled for 48 hr at ∼0 ◦ C, and filtered to recover the unconverted Cs 6 [P 2 W 5 O 23 ]·H 2 O, which was again used to synthesize Cs 7 [PW 10 O 36 ]·H 2 O. The product was characterized by FTIR spectroscopy [73]. 2.2.8 Synthesis of Na 20 [P 6 W 18 O 79 ]·37.5H 2 O To a solution of 50 g of Na 2 WO 4·2H 2 O in 50 mL of distilled water. 3.5 mL of (85%) H 3 PO 4 was added to the solution subsequently. This resulting solution was boiled until the final volume reached 50 mL. The solution was cooled and on cooling white crystalline precipitate was formed, which was recrystallized from water to get pure crystalline material. It was than characterized by FTIR and 31 P-NMR spectroscopies and was compared with the published data [74]. 2.2.9 Synthesis of K 12 [H 2 P 2 W 12 O 48 ]·24H 2 O 83 g of K 6 [P 2 W 18 O 62 ]·X H 2 O was dissolved in 300 mL of distilled water, and than a solution of 48.4 g (0.4 mol) of tris base in 200 mL water was added. The solution was left at room temperature for 30 minutes and then 80 g of solid KCl was added. After complete dissolution, a solution of 55.3 g (0.4 mol) of K 2 CO 3 in 200 mL of water was added. The resulting mixture was stirred for 15 minutes and a white precipitate appeared in due course of stirring. It was collected on a coarse sintered frit, dried under suction for 12 hours and washed couple of times with ethanol. The precipitate was then air dried for 3 days. It was characterized by FTIR and 31 P-NMR spectroscopies and was compared with the published data [75]. 22
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: 2.2 Preparation of starting materia
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
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
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whereas they are five-coordinated (
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investigated by scanning tunneling
Page 101 and 102:
3.8 The di-titanium substituted, lo
Page 103 and 104:
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
Page 113 and 114:
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
Page 141 and 142:
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
Page 153 and 154:
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
Page 169 and 170:
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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