Magnetoresistance Study on TPP[M(Pc)(CN)2]2 (M=Fe, Co, Fe0.30Co0.70) Salts

✍ Scribed by H. Tajima; N. Hanasaki; M. Matsuda; F. Sakai; T. Naito; T. Inabe

• Book ID: 102606802
• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 201 KB
• Volume: 168
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2002.9736

✦ Synopsis

The magnetoresistance study on TPP[M(Pc)(CN) 2 ] 2 (M=Fe, Co, Fe 0.30 Co 0.70 ) salts is reported. These three salts have similar columnar structures, nevertheless exhibit different electrical behaviors. TPP[Fe(Pc)(CN) 2 ] 2 exhibits anisotropic giant negative magnetoresistance, while TPP[Co(Pc)(CN) 2 ] exhibits large positive magnetoresistance. The alloyed compound, TPP[Fe 0.30 Co 0.70 (Pc)(CN) 2 ] 2 , also exhibits anisotropic negative magnetoresistance, although the decrease in the resistivity under the magnetic field is less than that of TPP[Fe(Pc)(CN) 2 ] 2 . The gtensor anisotropy in the [Fe(Pc)(CN) 2 ] unit qualitatively explains the field-orientation dependence of the negative magnetoresistance. Magnetic fluctuation associated with a weak-ferromagnetic transition is suggested as a possible origin of the giant negative magnetoresistance.