From Molecular to Two‐Dimensional Anderson Polyoxomolybdate: Synthesis, Crystal Structure, and Thermal Behavior of [{Ni(H₂O)₄}₂{Ni(OH)₆Mo₆O₁₈}]·4H₂O and [Ni(H₂O)₆][Ag₂{Ni(OH)₆Mo₆O₁₈}]·8H₂O

Abstract

Two 2D Anderson polyoxomolybdate‐based compounds, [{Ni(H2O)4}2{Ni(OH)6Mo6O18}]·4H2O (1) and [Ni(H2O)6][Ag2{Ni(OH)6Mo6O18}]·8H2O (2), were synthesized and characterized by elemental analysis, IR spectroscopy, SEM, and single‐crystal XRD. Their thermal behavior was studied by TGA, DSC, XRTD, and IR spectroscopy. Both 1 and 2 are arranged in 2D networks. In 1, [Ni(OH)6Mo6O18]4– Anderson units are covalently linked to each other by two different types of Ni2+, whereas in 2, the corresponding interactions are ensured exclusively by Ag+ ions. In addition, all the Ni2+ cations in 2 are located in interplanar positions and act selectively as counterions. Upon the addition of silver, the thermal stability of the Anderson anion is increased from 170 °C for pure nickel compound 1 up to 220 °C for mixed silver–nickel 2. Below 220 °C, 2 exhibits reversible hydration–dehydration processes with preservation of the Anderson anion structure. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The Anderson–Evans polyoxometalate: From inorganic building blocks via hybrid organic–inorganic structures to tomorrows “Bio-POM”

“…Monovalent, divalent and trivalent cations have been observed and sometimes the same species [95,114] acts as both the heteroatom and counter cation. Depending on the valence of the anions and cations the Anderson-Evans anion can act as a monodentate, bidentate or multidentate ligand [59,97].…”

Photoluminescence Properties of Two Closely Related Isostructural Series Based on Anderson-Evans Cluster Coordinated With Lanthanides [Ln(H2O)7{X(OH)6Mo6O18}]•yH2O, X = Al, Cr

“…The cluster assumes a near D 3d symmetry with dimensions ~8.6 × 8.6 × 2.7 Å and has been isolated with fifteen different heteroatoms till now [X: Al (Lee et al, 1991; Manikumari et al, 2002; Shivaiah et al, 2002; Martin et al, 2004; Shivaiah and Das, 2005; Liu et al, 2006; Dhara et al, 2007; Cao et al, 2008; Zhou et al, 2009), Cr (Perloff, 1970; An et al, 2006; Yu et al, 2006; Lee, 2007; Zhou and Yang, 2007; Shi D. et al, 2008; Shi D. M. et al, 2008; Zhang et al, 2008, 2014; Singh et al, 2010b, 2014; Li et al, 2011; Singh and Ramanan, 2011; Kumar et al, 2014a; Joo et al, 2015), Mn (He et al, 2012; Oms et al, 2012; Rosnes et al, 2012, 2013; Yan et al, 2012; Zhang et al, 2012, 2015a,b; Hutin et al, 2013; Ai et al, 2014; Yvon et al, 2014), Fe (Wu et al, 2001), Co (Nolan et al, 1996; Panneerselvam et al, 1996; Lee and Joo, 2000a; Lee et al, 2001; Martin et al, 2004), Ni (Lee et al, 2002; Liu et al, 2007; Liu F.-X. et al, 2008), Cu (Ito et al, 1989), Zn (Allen et al, 1997), Ga (Mensinger et al, 2008; Himeno et al, 2009), Te (Evans, 1948; Kondo et al, 1980; Robl and Frost, 1993a,b; Lorenzo-Luis et al, 1999; Drewes et al, 2004a,b; Charushnikova et al, 2005; Drewes and Krebs, 2005; Gao et al, 2007; Liu Y. et al, 2008; Yan et al, 2008), Rh (Ozawa et al, 1991), Pd (Ozawa et al, 1991), Sb (Ogawa et al, 1988; Yan et al, 2014), I (Kondo et al, 1980; Rosu and Weakley, 2000; An et al, 2005)and Pt (Lee and Sasaki, 1984; Lee, 1994; Lee and Joo, 2000b, …”

A New Strategy for the Synthetic Assembly of Inorganic–Organic Silver(I)-Polyoxometalate Hybrid Structures Employing Noncovalent Interactions between Theobromine Ligands

“…A multitude of silver(I) heteropolyoxometalate compounds was obtained following the same or similar procedures to the ones described above. − A slightly different synthetic strategy was applied for the isolation of Anderson anion containing materials. These anions contain central Lewis-acidic metal cations such as Ni 2+ or Cr 3+ , which are surrounded by a ring of six molybdate anions. − Thus, inorganic complex anions of the type [M(OH 6 )Mo 6 O 18 ] n − (M = Cr, Ni; n = 3 or 4) are readily assembled under mildly acidic conditions in aqueous solutions. Inorganic silver(I)-POMs are crystallized upon the addition of a silver(I) salt.…”