Chapter 4 - Jacobs University

Chapter 3 The Wheel-Shaped Cu 20
3.2 Synthesis
A sample of CuCl 2·2H 2 O (0.10 g, 0.60 mmol) was dissolved in a 1m LiCH 3 COO buffer solution
(20 mL) at pH 6.0, then K 28 Li 5 [H 7 P 8 W 48 O 184 ]·92H 2 O (0.37 g 0.025 mmol) (synthesized
according to ref 17b) was added. This solution was heated to 80 o C for 1 h and after cooling to
room temperature it was filtered. The filtrate was allowed to evaporate in an open beaker at room
temperature. After 1–2 days a blue crystalline product started to appear. Evaporation was
allowed to continue until the solution level had approached the solid product, which was then
collected by filtration and air-dried. Yield: 0.11 g (30%). IR: 1137(sh), 1121(s), 1080(s),
1017(m), 979(sh), 951(sh), 932(s), 913(sh), 832(sh), 753(s), 681(s), 570(sh), 523(w), 470 (w)
cm -1 .Elemental analysis (%) calcd for K 12 Li 13 1·22H 2 O: K 3.2, Li 0.6, W 59.2, Cu 8.5, P 1.7;
found: K 3.4, Li 0.8, W 58.8, Cu 8.6, P 1.6.
Elemental analysis was performed by Kanti Labs Ltd. in Mississauga, Canada.
80
75
70
65
60
55
%Transmittance
50
45
40
35
30
25
20
15
1300
1200
1100
1000
900
800
Wavenumbers (cm-1)
700
600
500
Figure 3.1 FT-IR spectrum of 1a.
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