One-dimensional spin dynamics in a halogen-bridged mixed-valence palladium (II), (IV) complex studied by 1H NMR

✍ Scribed by Ryuichi Ikeda; Masaki Iida; Tetsuo Asaji; Ashutosh Ghosh; Masahiro Yamashita

• Book ID: 103035877
• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 519 KB
• Volume: 210
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)89103-o

✦ Synopsis

The 'H NMR spin-lattice relaxation time T, of [ Pd (chxn )>] [ PdBr2 (chxn)*] Br4 (chxn = 1 R,2R-cyclohexanediamine) in the solid state was measured between 90 K and room temperature at Larmor frequencies of I C-60 MHz. The presence of thermally activated diffusive spins formed on paramagnetic Pd"' sites along the halogen-bridged LD chain was revealed from the Larmor frequency dependence of T,. The diffusion rates were estimated to be 2X IO", 9X lo", and 6x 10" rad s-' at 303, 198 and 125 K, respectively. The rate observed around room temperature showed an Arrhenius-type temperature dependence with an activation energy of zz 1700 K. It is shown that the diffusive spin is delocalized over several Pd sites. The observed spin motion is attributable to the neutral soliton by referring to the electrical conductivity data.