Two 3D porous terbium(III) mucicate frameworks, {[Tb-2(Mu(2-))(3)(H2O)(2)]center dot 4H(2)O}(n) (1) and {[Tb(Mu(2-))(Ox(2-))(0.5)(H2O)]center dot H2O}(n) (2), have been synthesized under hydrothermal conditions by changing the pH of the reaction medium. Isostructural europium(III) and seven mixed terbium(III)-europium(III) mucicates were synthesized by doping different percentages of Eu-III under similar reaction conditions and unveiling different emission colors ranging from green to red under the same wavelength. Both dehydrated Tb-III metal-organic frameworks exhibit selective H2O vapor sorption over other solvent molecules (MeOH, MeCN, and EtOH) of less polarity and bigger size and have been correlated to the highly hydrophilic pore surfaces decorated with -OH groups and O atoms from the carboxyl groups of mucicate.