Four novel rare-earth (RE) and Sb-oxo clusters simultaneously bridging antimonotungstates (ATs) [H2N-(CH3)(2)](8) Na6H8 {[RE4(H2O)(6)Sb6O4](SbW10O37)(2) - (SbW8O31)(2)}center dot 24H(2)O [RE = Dy3+ (1), Er3+ (2), Y3+ (3), Ho3+ (4)] were triumphantly isolated by using Na-9[B-alpha-SbW9O33]center dot 19.5H(2)O, dimethylamine hydrochloride, SbCl3, and RE-(NO3)(3)center dot 6H(2)O in acidic aqueous solution. Their tetrameric polyoxoanions are all established by two [SbW10O37](11-) and two [B-alpha-SbW8O31](11-) segments encapsulating a RE-Sb heterometal [RE4(H2O)(6)Sb6O4](22+) cluster. Under the O -> W LMCT excitation at 268 nm of AT segments, RE ions in 1 and 2 can absorb the T-3(1u)->(1)A(1g) emission energy of AT segments, giving rise to the sensitization of AT segments to the emission of RE ions. Through the sensitization of AT segments, the emission intensities of RE ions in 1 and 2 are increased and lifetimes are prolonged. Photoluminescence and energy transfer measurements indicate that Dy3+ ions in 1 can obtain more energy from AT segments than to Er3+ ions in 2. Furthermore, the sensitization effects of AT segments to different f-f transitions of RE ions have been compared in 1 and 2. Under the sensitization of AT segments, the F-4(9/2) -> H-6(15/2) transition obtains the most energy compared with the F-4(9/2) -> H-6(13/2) and F-4(9/2)-> H-6(11/2) transitions in 1, and the H-2(11/2)-I-4(15/2) transition obtains more energy than the S-4(3/2) -> I-4(15/2) transition in 2. It seems that the better energy level match of T-3(1u)->(1)A(1g) transition of AT segments with f-f emission transitions of RE ions will lead to a stronger sensitization effect.