Chapter 4 - Jacobs University

Chapter 9
Unpublished Results
9.3.4 Synthesis of Cs 10 Na[Hf 6 (µ 3 -
O) 4 (OH) 4 (H 2 O) 2 (CH 3 COO) 5 (AsW 9 O 33 ) 2 ]·73H 2 O (23a)
A 0.493 g (0.2 mmol) of Na 9 [α-AsW 9 O 33 ] was dissolved in 20 mL of 0.5 M LiH 3 COO buffer
solution (pH 4.0), and then 0.128 g (0.4 mmol) of HfCl 4 was added. The solution was heated at
80 o C for 1h and filtered while hot. Then 1M CsCl (0.5 mL) solution was added after filtration.
Slow evaporation at room temperature led to the appearance of white crystalline product after
about one week. Evaporation was allowed to continue until the solution level approached the
solid product, which was filtered off and air-dried. Yield 0.18g. (60%). IR: 1637(m), 1617(m),
1577(m), 948(m), 874(s),784(m), 729(w), 693(w), 649(w), 457(m) cm -1 .
80
78
76
74
72
70
68
66
%Transmittance
64
62
60
58
56
54
52
50
48
46
44
1800
1600
1400
1200
1000
Wavenumbers (cm-1)
800
600
Figure 9.62 FTIR spectrum of 23a.
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