Hydrothermal Synthesis and Structural Characterization of the (CnH2n+6N2)[Mn3(HPO3)4] (n = 3−8) New Layered Inorganic−Organic Hybrid Manganese(II) Phosphites. Crystal Structure and Spectroscopic and Magnetic Properties of (C3H12N2)[Mn3(HPO3)4] | Publicación