Chemistry Reference
In-Depth Information
Fig. 1 Examples of charged AuNCs that fit the [Au
(0)
a
Au
(+1)
b
L
c
A
(
1)
d
n
H
+
]
z
formulation and
that have been analysed by both MS and X-ray crystallography: (a) [Au
5
(dppm)
4
-H
+
]
2+
(where
a
¼
2;
b
¼
3;
c
¼
4;
n
¼
1;
z
¼
+2) [
57
]; (b) [Au
13
(dppe)
5
Cl
2
]
3+
(where
a
¼
8;
b
¼
5;
c
¼
5;
d
¼
2;
z
¼
+3) [
58
]; (c) [Au
11
(dppe)
6
]
3+
(where
a
¼
8;
b
¼
3;
c
¼
6;
z
¼
+3) [
59
] and (d)
[Au
25
(SCH
2
CH
2
Ph)
18
]
+
(where
a
¼
6;
b
¼
19;
d
¼
18;
z
¼
+1) [
60
]. Non-coordinating counter
ions are omitted for clarity. Figures reproduced from (a)[
57
]; (b)[
58
]; (c)[
59
]; (d)[
60
]
Thus the net charge of the NC is given by Eq. (
6
):
z
¼
b
ðÞþ
þ
1
d
ðÞ
1
n
ð
6
Þ
Note that either L or A can be deprotonated to add a negative charge to the NC.
Figure
1
highlights some of the isolated charged AuNCs that have been struc-
turally characterised by both X-ray crystallography and MS. The NC [Au
5
L
1
4
-H]
2+
(Fig.
1a
) is interesting as it possesses a tetrahedral gold core with an exopolyhedral
Au(CH(PPh
2
)
2
) moiety formed via deprotonation of the dppm at the methylene
carbon.
Some of the strategies listed above for the manipulation of inorganic and
organometallic compounds that have no net charge have also been applied to
AuNCs that have no net charge. Most examples are for AuNCs with thiolate
ligands: (1) thiolate ligand possessing acidic protons can be further deprotonated,
