Two　new　three-dimensional　lanthanide-alkali-heterometallic　frameworks　assembled　from　Ln(III)　(Ln　=　Sm,　Dy),　Na(I),　and　isonicotinic　acid　ligand,　formulated　as　[NaLn(IN)3(NO3)]n　(Ln　=　Sm(1),　Dy(2),　IN-　=　isonicotinic　acid)],　were　obtained　as　single　phases　under　hydrothermal　conditions.　Compounds　1　and　2　are　isostructures　with　three-dimensional　frameworks,　which　are　the　rare　examples　of　lanthanide-alkali-heterometallic　compounds.　The　band　gaps　calculated　from　adsorption　spectra　reflect　their　semiconductor　natures.　Strong　luminescence　in　two　compounds　can　be　attributed　to　the　emissions　involved　in　Ln3+　centers.　Graphical　Abstract:　Two　new　three-dimensional　lanthanide-alkali-heterometallic　frameworks　assembled　from　Ln(III)　(Ln　=　Sm,　Dy),　Na(I),　and　isonicotinic　acid　ligand,　formulated　as　[NaLn(IN)3(NO3)]n　(Ln　=　Sm(1),　Dy(2),　IN-　=　isonicotinic　acid)],　were　synthesized　and　structurally　determined.　Their　band　gaps　luminescence　were　discussed.　[Figure　not　available:　see　fulltext.].　©　2013　Springer　Science+Business　Media　New　York.