Magnetic behavior of La{sub 2}CoMnO{sub 6−δ} crystal doped with Pb and Pt

Graphical abstract: Display Omitted Highlights: ► We present results on the growth of bulk La{sub 2}CoMnO{sub 6} crystals doped with Pb and Pt. ► Crystals were characterized by EDXA, magnetic measurements and Raman spectroscopy. ► According to the magnetic measurements the structure is predominantly Co/Mn ordered. ► The polarized Raman measurements further support this conclusion. ► The reduced T{sub C} reflects the imperfections in the composition and the Co/Mn ordering. -- Abstract: La{sub 2}CoMnO{sub 6−δ} crystal doped with Pb and Pt was successfully grown. The lattice parameters were determined by X-ray diffractometry, while polarized Raman spectroscopy and magnetic measurements were used to probe the Co/Mn positional order, and to suggest the most likely crystal and magnetic structures. The magnetic response of the crystal to ac- and dc-magnetic fields is discussed in terms of possible occupation of the crystallographic positions by the constituent ions and valence state disproportion in the Mn/Co ions. The results are explained within a framework of statistically random distributed Mn{sup 3+}-O-Mn{sup 4+} and Co{sup 2+}-O-Pt{sup 4+} chains within the predominantly ordered Co{sup 2+}/Mn{sup 4+} double perovskite structure.