From monomers to geometry-constrained molecules: one step further toward cyanide bridged wires.
We report on the synthesis and properties of a family of linear cyanide bridged mixed-valence heptanuclear complexes with the formula: trans-[L(4)Ru(II){(mu-NC)Fe(III)(NC)(4)(mu-CN)Ru(II)L'(4)(mu-NC)Fe(III)(CN)(5)}(2)](6-) (with L and L' a para substituted pyridine). We also report on the properties of a related pentanuclear complex. These oligomers were purified by size exclusion chromatography, characterized by electrospray ionization (ESI) mass spectrometry and elemental analysis, and their linear shape was confirmed by scanning tunneling microscopy (STM). These complexes present a rich electrochemistry associated with the seven redox active centers. The redox potential split of identical fragments indicates that there is considerable communication along the cyanide bridged backbone of the compounds, even for centers more than 3 nm apart. This small attenuation of the interaction at long distances make these cyanide bridged compounds good candidates for molecular wires. Interestingly, the extent of the communication depends on the relative energy of the fragments, as evaluated by their redox potentials, providing a guide for improvement of this interesting property.
Alborés
Pablo
P
Departamento de Química Inorgánica, Analitica y Química Fisica, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellon 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina.
Slep
Leonardo D
LD
Eberlin
Livia S
LS
Corilo
Yuri E
YE
Eberlin
Marcos N
MN
Benítez
Guillermo
G
Vela
Maria E
ME
Salvarezza
Roberto C
RC
Baraldo
Luis M
LM