A series of new alkaline-earth metal diphosphonate frameworks were successfully synthesized under solvothermal reaction condition (160 degrees C, 3 d) using 1-hydroxyethylidene-1,1-diphosphonic acid (CH3C(OH)(H2PO3)(2), hedpH(4)) as a diphosphonate building block and Mg(II), Ca(II), Sr(II), or Ba(II) ions as alkaline-earth metal ion centers in water, dimethylformamide, and/or EtOH media. These diphosphonate frameworks, (H2NMe2)(4)[Mg(hedpH(2))(3)] 3H(2)O (1), (H2NMe2)(2)[Ca(hedpH(2))(2)] (2), (H2NMe2)(2)[Sr-3(hedpH(2))(4)(H2O)(2)] (3), and [Ba-3(hedpH(2))(3)] H2O (4) exhibited interesting structural topologies (zero-, one-, two-, and three-dimensional (0D, 1D, 2D, and 3D, respectively)), which are mainly depending on the metal ions and the solvents used in the synthesis. The single-crystal analysis of these newly synthesized compounds revealed that 1 was a 0D molecule, 2 has 1D chains, 3 was a 3D molecule, and 4 has 2D layers. All compounds were further characterized using thermogravimetric analysis, solid-state (31)P NMR, powder X-ray diffraction analysis, UV-vis spectra, and infrared spectroscopy. In addition, Eu(III)- and Tb(III)-doped compounds of 1-4, namely, (H2NMe2)(4)[Ln(x)Mg(1-)x(hedpH(2))(2)(hedpH(2-x))] 3H(2)O (1Ln), (H2NMe2)(2)[LnxCa(1-x)(hedpH(2))(hedpH(2-x))] (2Ln), (H2NMe2)(2)[Ln(x)Sr(3-x)(hedpH(2))(3)(hedpH(2-x))(H2O)(2)] (3Ln), and [Ln(x)Ba(3-x)(hedpH(2))(2)(hedpH(2-x))] H2O (4Ln) (where Ln = Eu, Tb), were synthesized, and their photoluminescence properties were studied. The quantum yield of 1Eu-4Eu was measured with reference to commercial red phosphor, Y2O2S:Eu3+ (YE), and the quantum yield of terbium-doped compounds 1Tb-4Tb was measured with reference to commercial green-emitting phosphor CeMgAl10O17:Tb3+. Interestingly, the compound 2Eu showed very high quantum yield of 92.2%, which is better than that of the reference commercial red phosphor, YE (90.8%).