Syntheses and structural researches of nine-coordinate (NH 4) 2[Er III(Httha)]·6H 2O and ten-coordinate (CH 3NH 3) 3[Nd III(ttha)]·CH 3NH 2·4H 2O

Abstract

The crystal and molecular structures of the (NH 4) 2[Er III(Httha)]·6H 2O (ttha=triethylenetetraminehexaacetic acid) and (CH 3NH 3) 3[Nd III(ttha)]·CH 3NH 2·4H 2O complexes have been determined by single-crystal X-ray structure analyses. The crystal of the (NH 4) 2[Er III(Httha)]·6H 2O complex belongs to monoclinic crystal system and P2(1)/ c space group. The crystal data are as follows: a=1.0324(4) nm, b=1.2745(4) nm, c=2.3170(8) nm, β=91.014°, V=3.0482(18) nm 3, Z=4, M=800.84, D c =1.743 g cm −3, μ=2.839 mm −1 and F(000)=1624. The final R and wR values are 0.0261 and 0.0696 for 5384 [ I>2.0 σ( I)] unique reflections, and 0.0329 and 0.0719 for all 12442 reflections, respectively. The complex [Er III(Httha)] 2− anion has a nine-coordinate pseudo-monocapped square antiprismatic structure in which the nine coordinate atoms, four N and five O are from one ttha ligand. The crystal of the (CH 3NH 3) 3[Nd III(ttha)]·CH 3NH 2·4H 2O complex belongs to triclinic system and P 1 ̄ space group. The crystal data are as follows: a=1.0772(3) nm, b=1.2194(4) nm, c=1.4505(4) nm, α=105.502(4)°, β=98.225(5)°, γ=99.906(5)°, V=1.7723(9) nm 3, Z=2, M=831.98, D c =1.559 g cm −3, μ=1.542 mm −1 and F(000)=862. The final R and wR are 0.0291 and 0.0786 for 6224 [ I>2.0 σ( I)] unique reflections, and 0.0348 and 0.0823 for all 7398 reflections, respectively. The complex [Nd III(ttha)] 3− anion has a ten-coordination structure with distorted bicapped square antiprismatic prism in which the ttha acts as a decadentate ligand with four N atoms of amino groups and six O atoms of carboxylic groups.