Synthesis and crystal structure of a novel one-dimensional halogen-bridged nickel(III)-X-nickel(III) compound, {[Ni(R,R-chxn)2Br]Br2}.infin.

Soliton Excitations in Halogen-Bridged Mixed-Valence Binuclear Metal Complexes

“…The PtX compounds [4][5][6] have mixed-valence ground states exhibiting intense and dichroic charge-transfer absorption, strong resonance enhancement of Raman spectra and luminescence with large Stokes shift. On the other hand, the NiX compounds [7][8][9] possess monovalence magnetic ground states due to the strong on-site d-d Coulomb interaction. Substituting the bridging halogens, ligand molecules and counter ions as well as the transition metals, we can widely tune the electronic states of MX chains [10].…”

Exploration of Boundary between Charge-Density-Wave and Mott–Hubbard States in Quasi-One-Dimensional Halogen-Bridged Metal Complexes

“…Figure 17a. 13 In this structure, the Ni 3+ ions and Br ¹ ions alternate with equivalent NiBr distances, and the four N atoms of the two chxn ligands coordinating to each Ni 3+ ion in the equatorial positions producing a strong ligand field. Each NiBrNi 1D chain is hydrogen-bridged between the amino-protons of chxn and counter Br ions along the chains, as well as over the chains, forming two-dimensional hydrogenbond networks.…”

“…13 In the Ni complexes, many attractive physical properties have been reported such as gigantic third-order-nonlinear optical susceptibility, 14 spin-Peierls transition, 15 etc. To date, more than 300 MX-chain complexes have been reported.…”

“…Recently, there has been much effort for controlling the macroscopic properties by the molecular bistability through cooperative phenomena. 13 In one-dimensional systems especially, dynamics can be expected owing to the bistability of molecules because cooperativity is weaker than three-dimensional systems. From this point of view, we have studied the charge dynamics in quasi-onedimensional halogen-bridged metal complexes (Figure 1) by using charge bistability of metal ions.…”

Ground-State Properties of a Peierls–Hubbard Triangular Prism

“…15 Platinum-halide single-chain compounds such as Wolffram's red salt 16 [Pt(ea) 4 Cl]Cl 2 ·2H 2 O (ea = ethylamine = C 2 H 7 N) have a Peierls-distorted mixed-valent ground state, whereas their nickel analogs 17,18 consist of Mott-insulating monovalent regular chains. In between are palladium halides, whose ground states can be tuned optically 19,20 and electrochemically.…”