“…A search of the Cambridge Structural Database (CSD, Version 5.36, with updates to November 2014; Groom & Allen, 2014) revealed that: (i) the structure of (I) is the first example of a three-coordinated Hg II complex with a Cl 2 Hg-O P[N(C)(C)] 3 segment; (ii) there are only two phosphoric triamide Hg II structures present, namely bis(dimesylamide-N)(hexamethylphosphoramide-O)mercury(II) (CSD refcode JUWNOE; Blaschette et al, 1993) and bis( 3 -hexamethylphosphoramide)tris( 2 -perfluoro-o-phenylene)trimercury(II) (CAMFEC; Tikhonova et al, 2002), the preparation of both of which used the commercial material [(CH 3 ) 2 N] 3 PO; (iii) the (C 5 H 10 N) 3 PO ligand appears in only two complex structures, namely tris(isothiocyanato)tris(tripiperidinylphosphine oxide)praseodymium(III) (MALMAO; da Silva et al, 2005) and bis(nitrato-2 O,O 0 )dioxidobis(tripiperidinylphosphine oxide-O)uranium (LOPVUH; de Aquino et al, 2000). A search of the Cambridge Structural Database (CSD, Version 5.36, with updates to November 2014; Groom & Allen, 2014) revealed that: (i) the structure of (I) is the first example of a three-coordinated Hg II complex with a Cl 2 Hg-O P[N(C)(C)] 3 segment; (ii) there are only two phosphoric triamide Hg II structures present, namely bis(dimesylamide-N)(hexamethylphosphoramide-O)mercury(II) (CSD refcode JUWNOE; Blaschette et al, 1993) and bis( 3 -hexamethylphosphoramide)tris( 2 -perfluoro-o-phenylene)trimercury(II) (CAMFEC; Tikhonova et al, 2002), the preparation of both of which used the commercial material [(CH 3 ) 2 N] 3 PO; (iii) the (C 5 H 10 N) 3 PO ligand appears in only two complex structures, namely tris(isothiocyanato)tris(tripiperidinylphosphine oxide)praseodymium(III) (MALMAO; da Silva et al, 2005) and bis(nitrato-2 O,O 0 )dioxidobis(tripiperidinylphosphine oxide-O)uranium (LOPVUH; de Aquino et al, 2000).…”