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The coupling between spins and charge disproportionation states has been investigated in the LaCa2Fe3O9 oxide with neutron powder diffraction. This A -site layer ordered triple perovskite LaCa2Fe3O9 undergoes charge disproportionation on cooling and shows two different charge ordering patterns. At 230 K, Fe 3.67+ disproportionates into a 2:1 ratio of Fe3+: Fe5+, which order in a layered manner along the <010> direction of the pseudocubic unit cell. At lower temperatures(T< 170 K), the charge ordering pattern changes to a layered arrangement along the <111> direction. Neutron powder diffraction data show that in the intermediate temperature range(170 K layered magnetic structure. [ABSTRACT FROM AUTHOR]