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Members of the Na „Li, MnFe3 (PO), series, with the alluaudite structure type, were synthesized by solid-state reaction in air. The crystal structure refinement of the NaMnFe (PO), end-member (space group C2/c, Z= 4, a= 12.018 (2), b= 12.565 (3), c= 6415 (1) A, ß= 114.33 (3)"), a synthetic compound with a chemical composition corresponding to the idealized composition of the Buranga alluaudite, was carried out to R,= 0.026. The following cationic distribution was observed: Na"+ D in A (1) and A (2)'(T denotes lattice vacancies), Mn** in M (1), Fe"--Fe** in M (2). The A (2)'site exhibits a distorted gable disphenoid morphology and is found at the (0, y, Z)(y= 0) position in channel 2 of the alluaudite structure. The crystal structure of Na, Li, MnFe (PO),(space group C2/c, Z= 4, a= 11.988 (2), b= 12.500 (3), c= 6.392 (1) Á, ß= 114.67 (3)"), refined to R,= 0,034, leads to the cationic distribution: Li “+ Na"+ D in A (2)", Na"+ Din A …