Single crystal synthesis and anisotropic magnetization of TMSb2O4 (TM = Mn, Co, Ni)

The synthesis, single crystal growth and anisotropic magnetization study of high-quality, single crystals in the TM Sb 2 O 4 ( TM = Mn, Co, Ni) series are reported. Columnar crystals, several millimeters in length, crystallized in the tetragonal space group , P 4 2 / mbc , were obtained by a high-temperature hydrothermal method . Magnetization studies of crystals aligned in an external magnetic field respective to the principal crystallographic axes were performed and allowed study of the 1D intrachain interactions of octahedral TM 2+ edge-shared chains along the c -axis, as well as the wider 3D magnetic superstructure arising from through-space interchain interactions. Magnetic susceptibility measurements revealed strong ordering behavior when fields were applied along the chains that were contrasted by a more muted response for chain orientations normal to the applied field. The field- and cooling-dependent ordering transitions found in the CoSb 2 O 4 system when a field is applied perpendicular to the S = 3/2 Co 2+ chains is complex and highlights the highly anisotropic spin exchange coupling between the intrachain, nearest-neighbor (NN), and next-nearest-neighbor (NNN) interactions. Specific heat measurements revealed a field-dependent secondary ordering feature at 13.5 K that, on application of 90 kOe applied fields, is suppressed and broadened, which matches behavior seen in the field-dependent susceptibility. The anisotropic magnetic coupling provides a roadmap for additional study of single crystals of other 1D chains. Hydrothermal crystal growth and anisotropic magnetic characterization of TM Sb 2 O 4 ( TM = Mn, Co, Ni). • Single crystals of TM Sb 2 O 4 ( TM = Mn, Co, Ni) were grown hydrothermally, enabling anisotropic magnetization measurements. • Fields along the chains elicited a strong magnetic response, lessening in fields normal to the chain direction. • Multiple magnetic transitions were observed in CoSb 2 O 4 and investigated further using specific heat measurements. • Intrachain and interchain interactions were evaluated.