Utilization of binary information encoded in the charge configuration of quantum-dot cells (the quantum-dot cellularautomata, QCA,
paradigm) requires molecule-sized dots for room tem
perature o
peration. Molecular QCA cells aremixed-valence com
plexes,
and the evaluation
and functionalization of an unsymmetrical heterobinuclear, two-dot,Fe-Ru molecular QCA cell is described. The solid state structures of
trans-RuCl(d
ppm)
2(C
![](/images/entities/tbd1.gif)
CFc) (
1) (d
ppm =methylbis(di
phenyl
phos
phane), Fc = (
5-C
5H
5)Fe(
5-C
5H
4))
and mixed-valence [
trans-RuCl(d
ppm)
2(C
![](/images/entities/tbd1.gif)
CFc)][BF
4](
1a) as well as XPS
and s
pectrosco
pic data suggest class II behavior suitable for the intended a
pplication. Utilizationof the trans-Cl
position of
1 permits functionalization for surface binding. Two "tailed" com
plexes of
1,
trans-Ru(d
ppm)
2(C
![](/images/entities/tbd1.gif)
CFc)(C
![](/images/entities/tbd1.gif)
CPhOCH
3) (
2)
and trans-[Ru(d
ppm)
2(C
![](/images/entities/tbd1.gif)
CFc)(N
![](/images/entities/tbd1.gif)
CCH
2CH
2NH
2)][PF
6] (
3), have been
pre
pared
and characterized. The solid state structure of
3 and multinuclear NMR ex
periments define the structures. In addition,the s
pectrosco
pic
pro
perties of all com
plexes
and their mixed-valence s
pecies are used to define the effect of thesubstituent "tail" on mixed-valence
pro
perties. Further, the electrochemistry of these com
pounds
permits assessmentof the extent of
perturbation of the substituents on the com
pro
portionation constants
and overall electrochemicalstability. The com
plexes
possess
pro
perties necessary for c
andidate QCA molecules.