Luminescence homoleptic cyclic tetranuclear [Ln4(BTFA)10(μ3-OH)2(H2O)4] complexes (Ln = Eu or Tb)

For Eu3+- or Tb3+-centered luminescent tetranuclear complex [Ln4(BTFA)10(μ3-OH)2(H2O)4] (Ln = Eu, 2 or Tb, 3) with the η2-Mode I and the μ-(O)-η2-bridging Mode II bonding of the (BTFA)− ligands, two μ3-(OH)− anions, two μ1-coordinating H2O and two μ2-bridging H2O molecules surrounded from the four Ln3+ ions, color-purity red-light (ΦLEu = 20.1%) for complex 2 while few near-white-light (Φem = 6.4%) for complex 3 are exhibited, respectively.81