Synthesis, structure, and magnetic properties of Li-doped manganese-phthalocyanine, Li(x)[MnPc] (0 < or = x < or = 4).
We report on the first synthesis of Li-intercalated manganese-phthalocyanine (MnPc) in the bulk form and on the evolution of the structural and magnetic properties as a function of Li concentration, x. We find that solid beta-MnPc, which comprises rodlike assemblies of individual planar molecules, is best described as a glassy one-dimensional ferromagnet without three-dimensional ordering and that it can be quasi-continuously intercalated with Li up to x = 4, forming an isosymmetrical series of Li(x)[MnPc] phases. Inserted Li+ ions strongly bond to pyrrole-bridging nitrogen atoms of the Pc rings, thereby disrupting the ferromagnetic Mn-N(a)...Mn superexchange pathways. This gradually induces a crossover of the intrachain exchange interactions from ferromagnetic to antiferromagnetic as the doping level, x, increases coupled with a spin-state transition of the Mn2+ ions from intermediate spin, S = 3/2, to high spin, S = 5/2.
Taguchi
Yasujiro
Y
Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan. taguchi@imr.tohoku.ac.jp
Miyake
Toshiaki
T
Margadonna
Serena
S
Kato
Kenichi
K
Prassides
Kosmas
K
Iwasa
Yoshihiro
Y
D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry*; D054833:Isoindoles; D008094:Lithium / Q000737:chemistry*; D008280:Magnetics; D008345:Manganese / Q000737:chemistry*; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D014961:X-Ray Diffraction
D007211:Indoles; D054833:Isoindoles; D009942:Organometallic Compounds; D008345:Manganese; D008094:Lithium; C013647:phthalocyanine