Next Article in Journal
Intramolecular Spin State Locking in Iron(II) 2,6-Di(pyrazol-3-yl)pyridine Complexes by Phenyl Groups: An Experimental Study
Previous Article in Journal
Closing the Circle of the Lanthanide-Murexide Series: Single-Molecule Magnet Behavior and Near-Infrared Emission of the NdIII Derivative
Open AccessArticle

Mononuclear Lanthanide(III)-Salicylideneaniline Complexes: Synthetic, Structural, Spectroscopic, and Magnetic Studies

Department of Chemistry, University of Patras, 26504 Patras, Greece
Departament de Quimica Inorgànica i Orgànica, Secció Inorgànica and Institut de Nanociencia i Nanotecnologia (IN2UB), Universitat de Barcelona, Marti i Franquès 1-11, 08028 Barcelona, Spain
Department of Solar Energy and Environmental Physics, Ben-Gurion University of the Negev, Midreshet Sede Boqer 8499000, Israel
Department of Fisheries and Aquaculture Technology, Technological Educational Institute of Western Greece, 30200 Messolonghi, Greece
Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, 15310 Aghia Paraskevi Attikis, Greece
ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Nanoscience and Nanotechnology, Castelldefels, 08860 Barcelona, Spain
Institute of Chemical Engineering Sciences, Foundation for Research and Technology-Hellas (FORTH/ICE-HT), Platani, PO Box 1414, 26504 Patras, Greece
Authors to whom correspondence should be addressed.
This article is dedicated to Professor Emeritus Christopher Landee, a great physicist whose collaboration with chemists had led to exciting results in the area of the magnetic properties of coordination complexes.
Magnetochemistry 2018, 4(4), 45;
Received: 26 August 2018 / Revised: 18 September 2018 / Accepted: 21 September 2018 / Published: 7 October 2018
The reactions of hydrated lanthanide(III) [Ln(III)] nitrates and salicylideneaniline (salanH) have provided access to two families of mononuclear complexes depending on the reaction solvent used. In MeCN, the products are [Ln(NO3)3(salanH)2(H2O)]·MeCN, and, in MeOH, the products are [Ln(NO3)3(salanH)2(MeOH)]·(salanH). The complexes within each family are proven to be isomorphous. The structures of complexes [Ln(NO3)3(salanH)2(H2O)]·MeCN (Ln = Eu, 4·MeCN_Eu, Ln = Dy, 7·MeCN_Dy; Ln = Yb, 10·MeCN_Yb) and [Ln(NO3)3(salanH)2(MeOH)]·(salanH) (Ln = Tb, 17_Tb; Ln = Dy, 18_Dy) have been solved by single-crystal X-ray crystallography. In the five complexes, the LnIII center is bound to six oxygen atoms from the three bidentate chelating nitrato groups, two oxygen atoms from the two monodentate zwitterionic salanH ligands, and one oxygen atom from the coordinated H2O or MeOH group. The salanH ligands are mutually “cis” in 4·MeCN_Eu, 7·MeCN_Dy and 10·MeCN_Yb while they are “trans” in 17_Tb and 18_Dy. The lattice salanH molecule in 17_Tb and 18_Dy is also in its zwitterionic form with the acidic H atom being clearly located on the imine nitrogen atom. The coordination polyhedra defined by the nine oxygen donor atoms can be described as spherical tricapped trigonal prisms in 4·MeCN_Eu, 7·MeCN_Dy, and 10·MeCN_Yb and as spherical capped square antiprisms in 17_Tb and 18_Dy. Various intermolecular interactions build the crystal structures, which are completely different in the members of the two families. Solid-state IR data of the complexes are discussed in terms of their structural features. 1H NMR data for the diamagnetic Y(III) complexes provide strong evidence that the compounds decompose in DMSO by releasing the coordinated salanH ligands. The solid complexes emit green light upon excitation at 360 nm (room temperature) or 405 nm (room temperature). The emission is ligand-based. The solid Pr(III), Nd(III), Sm(III), Er(III), and Yb(III) complexes of both families exhibit LnIII-centered emission in the near-IR region of the electromagnetic spectrum, but there is probably no efficient salanH→LnIII energy transfer responsible for this emission. Detailed magnetic studies reveal that complexes 7·MeCN_Dy, 17_Tb and 18_Dy show field-induced slow magnetic relaxation while complex [Tb(NO3)3(salanH)2(H2O)]·MeCN (6·MeCN_Tb) does not display such properties. The values of the effective energy barrier for magnetization reversal are 13.1 cm−1 for 7·MeCN_Dy, 14.8 cm−1 for 17_Tb, and 31.0 cm−1 for 18_Dy. The enhanced/improved properties of 17_Tb and 18_Dy, compared to those of 6_Tb and 7_Dy, have been correlated with the different supramolecular structural features of the two families. The molecules [Ln(NO3)3(salanH)2(MeOH)] of complexes 17_Tb and 18_Dy are by far better isolated (allowing for better slow magnetic relaxation properties) than the molecules [Ln(NO3)3(salanH)2(H2O)] in 6·MeCN_Tb and 7·MeCN_Dy. The perspectives of the present initial studies in the Ln(III)/salanH chemistry are discussed. View Full-Text
Keywords: lanthanide(III)-salicylideneaniline complexes; single-ion lanthanide(III) magnets; photoluminescence studies; near-IR emission; single-crystal X-ray crystallography lanthanide(III)-salicylideneaniline complexes; single-ion lanthanide(III) magnets; photoluminescence studies; near-IR emission; single-crystal X-ray crystallography
Show Figures

Graphical abstract

MDPI and ACS Style

Mylonas-Margaritis, I.; Maniaki, D.; Mayans, J.; Ciammaruchi, L.; Bekiari, V.; P. Raptopoulou, C.; Psycharis, V.; Christodoulou, S.; Escuer, A.; P. Perlepes, S. Mononuclear Lanthanide(III)-Salicylideneaniline Complexes: Synthetic, Structural, Spectroscopic, and Magnetic Studies. Magnetochemistry 2018, 4, 45.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

Back to TopTop