Structural study of electronic states in quasi-one-dimensional halogen-bridged mixed-metal complexes [Ni(1-x)Pd(x)(chxn)(2)Br]Br(2)

Charge-bistable Pd(iii)/Pd(ii,iv) coordination polymers: phase transitions and their applications to optical properties

This paper reviews the recent progress in charge-bistable Pd(iii)/Pd(ii,iv) coordination polymers (MX chains). The temperature-, pressure- and photo-induced phase transitions have been demonstrated, proposing MX chains as a material for optical switching devices.

Palladium(III) in Synthesis and Catalysis

While the organometallic chemistry of Pd in its (0), (+II), and (+IV) oxidation states is well-established, organometallic Pd(III) chemistry remains widely unexplored. Few characterized Pd(III) complexes are known, which has inhibited detailed study of the organometallic chemistry of Pd(III). In this review, the potential roles of both mono- and dinuclear Pd(III) complexes in organometallic chemistry will be discussed. While not widely recognized, Pd in the (+III) oxidation state may play a significant role in a variety of known Pd-catalyzed reactions.

Stabilization of Pd(III) states in nano-wire coordination complexes

In spite of a long history of quasi-one-dimensional halogen-bridged complexes (MX-chains), all Pt and Pd complexes form the charge-density wave (CDW) state (-X...M(II)...X-M(IV)-X...), while all Ni complexes form Mott-Hubbard (MH) states (-X-Ni(III)-X-Ni(III)-X-), without exception. We have succeeded in stabilizing the Pd(iii) MH state for the first time by utilizing the following two methods: partial substitution with Ni(iii) ions, [Ni(1-x)Pd(x)(chxn)(2)Br]Br(2), and chemical pressure via long alkyl chains introduced as counter-anions, [Pd(en)(2)Br](C(n)-Y)(2).H(2)O. In both systems, it has been revealed that the electronic state of bromo-bridged Pd compounds are determined by the PdPd distances, in other words, CDW and MH states are stabilized when PdPd distances are longer and shorter than 5.26 A, respectively.