TY - JOUR
T1 - Synthesis and structure of dimeric anthracene-9-carboxylato bridged dinuclear erbium(III) complex, [Er2(9-AC)6(DMF)2(H2O)2]
AU - Kusrini, Eny
AU - Adnan, Rohana
AU - Saleh, Muhammad I.
AU - Yan, Lim Kong
AU - Fun, Hoong Kun
PY - 2009/5/1
Y1 - 2009/5/1
N2 - We study the influence of the bulky aromatic rings, e.g. anthracence-9-carboxylic acid (9-ACA) with a large conjugated π-system on the structure and spectroscopic properties of [Er2(9-AC)6(DMF)2(H2O)2] complex where 9-AC = anthracence-9-carboxylato and DMF = N,N′-dimethylformamide. The complex has been prepared from the erbium chloride and 9-ACA in the mixture of H2O:DMF solution (4:1, v/v) followed by pH adjustment to 6. The complex is crystallized in a monoclinic system with space group P21/n. The two Er(III) ions are double bridged by the deprotonated carboxyl groups of two 9-AC anions (O1 and O1A), forming an eight-coordination number. The chelating bidentate (O,O), chelating-bridging tridentate (O,O,O′) and monodentate of 9-AC anions are observed in the dinuclear [Er2(9-AC)6(DMF)2(H2O)2] complex. The Er-Er distance is 4.015 Å in the dimeric unit. Intramolecular O-H⋯O and C-H⋯O hydrogen bonds as well as numerous of intermolecular C-H⋯π interactions between the anthracene rings by edge-to-face interactions linked the dinuclear dimeric units into two-dimensional supramolecular network in a propeller-arrangement. Electronic absorption spectra of the Er(III) complex and its salt were measured. The emission spectrum of the complex is composed of a broad band due to the emission of intraligand π* → π transition from the 9-AC anions and a shoulder peak originating from the 4f-4f emission transition of the Er(III) ions. The complex has a high thermal stability which can be attributed to the effectively increase the rigidity of the 9-AC anions.
AB - We study the influence of the bulky aromatic rings, e.g. anthracence-9-carboxylic acid (9-ACA) with a large conjugated π-system on the structure and spectroscopic properties of [Er2(9-AC)6(DMF)2(H2O)2] complex where 9-AC = anthracence-9-carboxylato and DMF = N,N′-dimethylformamide. The complex has been prepared from the erbium chloride and 9-ACA in the mixture of H2O:DMF solution (4:1, v/v) followed by pH adjustment to 6. The complex is crystallized in a monoclinic system with space group P21/n. The two Er(III) ions are double bridged by the deprotonated carboxyl groups of two 9-AC anions (O1 and O1A), forming an eight-coordination number. The chelating bidentate (O,O), chelating-bridging tridentate (O,O,O′) and monodentate of 9-AC anions are observed in the dinuclear [Er2(9-AC)6(DMF)2(H2O)2] complex. The Er-Er distance is 4.015 Å in the dimeric unit. Intramolecular O-H⋯O and C-H⋯O hydrogen bonds as well as numerous of intermolecular C-H⋯π interactions between the anthracene rings by edge-to-face interactions linked the dinuclear dimeric units into two-dimensional supramolecular network in a propeller-arrangement. Electronic absorption spectra of the Er(III) complex and its salt were measured. The emission spectrum of the complex is composed of a broad band due to the emission of intraligand π* → π transition from the 9-AC anions and a shoulder peak originating from the 4f-4f emission transition of the Er(III) ions. The complex has a high thermal stability which can be attributed to the effectively increase the rigidity of the 9-AC anions.
KW - Anthracence-9-carboxylic acid
KW - Crystal structure
KW - Dimeric complex
KW - Erbium
UR - http://www.scopus.com/inward/record.url?scp=59449097222&partnerID=8YFLogxK
U2 - 10.1016/j.saa.2008.12.011
DO - 10.1016/j.saa.2008.12.011
M3 - Article
C2 - 19167268
AN - SCOPUS:59449097222
VL - 72
SP - 884
EP - 889
JO - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
JF - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
SN - 1386-1425
IS - 4
ER -