Chapter 4 - Jacobs University

Chapter 9
Unpublished Results
9.3.3 Synthesis of K 12 [{Zr(O 2 )(GeW 11 O 39 )} 2 ]·25H 2 O (22a)
A 0.644g (0.2 mmol) sample of K 8 [α-GeW 11 O 39 ]·14H 2 O was dissolved in 20 mL 1M KCH 3 COO
buffer solution (pH 4.8), and then 0.046g (0.2 mmol) of ZrCl 4 was added. During the reaction 5-
10 drops of 30% H 2 O 2 was introduced into the reaction mixture. The solution was heated to 80
o C for 30 min and filtered while still hot. Then, 6 drops of 1M KCl were added after filtration.
Slow evaporation at room temperature led to the appearance of yellowish crystalline product
within one day. The evaporation was allowed to continue until the solution level approached the
solid product which was then collected by filtration and air dried. Yield: 0.46g (64.15%). IR:
959(s), 872(s), 809 (m), 770(m), 712(w), 670(sh), 530(w) ,453(m), 422(sh) cm -1 .
60
55
50
45
%Transmittance
40
35
30
25
20
15
1000
900
800
700
Wavenumbers (cm-1)
600
500
Figure 9.59 FTIR spectrum of 22a.
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