Single-molecule magnet behavior in 2,2’-bipyrimidine-bridged dilanthanide complexes

• Wen Yu,
• Frank Schramm,
• Eufemio Moreno Pineda,
• Yanhua Lan,
• Olaf Fuhr,
• Jinjie Chen,
• Hironari Isshiki,
• Wolfgang Wernsdorfer,
• Wulf Wulfhekel and
• Mario Ruben

Beilstein J. Nanotechnol. 2016, 7, 126–137, doi:10.3762/bjnano.7.15

• Strasbourg, 23 rue du Loess, BP 43, F-67034 Strasbourg Cedex 2, France 10.3762/bjnano.7.15 Abstract A series of 2,2’-bipyrimidine-bridged dinuclear lanthanide complexes with the general formula [Ln(tmhd)3]2bpm (tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionate, bpm = 2,2’-bipyrimidine, Ln = Gd(III), 1; Tb(III

• with the presence of hysteresis loops. Keywords: bipyrimidine; diketone; hysteresis; lanthanide; magnetism; Introduction The application of magnetic molecular compounds within molecular electronic devices is combined in the progressive field of spintronics. An anisotropic spin is confined by the

• date, the largest anisotropy barrier observed in a transition metal SMM is 226 cm−1 in the Fe(II) complex [Fe(C(SiMe3)3)2]− [10]. Recently, molecular compounds employing lanthanide ions led to a considerable increase in strength of molecular magnets due to the observation of the SMM character at the

Sub-monolayer film growth of a volatile lanthanide complex on metallic surfaces

• Hironari Isshiki,
• Jinjie Chen,
• Kevin Edelmann and
• Wulf Wulfhekel

Beilstein J. Nanotechnol. 2015, 6, 2412–2416, doi:10.3762/bjnano.6.248

• , Germany 10.3762/bjnano.6.248 Abstract We deposited a volatile lanthanide complex, tris(2,2,6,6-tetramethyl-3,5-heptanedionato)terbium(III), onto metal surfaces of Cu(111), Ag(111) and Au(111) in vacuum and observed well-ordered sub-monolayer films with low temperature (5 K) scanning tunneling microscopy

• contamination of the surface. This new rare-earth-based class of molecules broadens the choice of molecular magnets to study with scanning tunneling microscopy. Keywords: β-diketonate; molecular films; scanning tunneling microscopy; terbium; volatile lanthanide complex; Introduction Several carefully designed

• result of the quantum mechanical interaction of the local magnetic moment and the ligand field [1]. Lanthanide-based SMMs have attracted much interest due to the potentially huge energy barrier for the reversal of magnetization [2]. This is an advantage from an applications viewpoint for magnetic storage

Silica-coated upconversion lanthanide nanoparticles: The effect of crystal design on morphology, structure and optical properties

• Uliana Kostiv,
• Miroslav Šlouf,
• Hana Macková,
• Alexander Zhigunov,
• Hana Engstová,
• Katarína Smolková,
• Petr Ježek and
• Daniel Horák

Beilstein J. Nanotechnol. 2015, 6, 2290–2299, doi:10.3762/bjnano.6.235

• the Czech Republic, Vídeňská 1083, 142 20 Prague 4, Czech Republic 10.3762/bjnano.6.235 Abstract NaYF4:Yb3+/Er3+ nanoparticles were synthesized by thermal decomposition of lanthanide trifluoroacetates using oleylamine (OM) as both solvent and surface binding ligand. The effect of reaction temperature

• enable further functionalization and increase biocompatibility and stability in aqueous media, preventing particle aggregation. Keywords: lanthanide; nanoparticles; oleylamine; silica; upconversion; Introduction Due to their unique physicochemical properties, nanometer-scale materials are finding

• tracking [8], bioimaging [9] and photodynamic therapy [10]. Lanthanide-doped upconversion nanoparticles emit visible light upon excitation by near-IR light (NIR). Compared with organic dyes and semiconductor quantum dots, upconversion nanoparticles have attractive chemical and optical properties, as well

Molecular materials – towards quantum properties

• Mario Ruben

Beilstein J. Nanotechnol. 2015, 6, 1485–1486, doi:10.3762/bjnano.6.153

• exploitation of the quantum properties. Devices based on single, or small numbers of, molecules, could speed up information treatment or allow for processing schemes that have not been possible to date. In a series of recent publications, it could be shown that magnetic molecules, in particular lanthanide

• coupling between molecular qubits as required by scalability for logical quantum gate operations. We have gathered in the Thematic Series contributions dealing with the magnetic properties of molecules, partially under use of lanthanide metal ions und their coordination under surface confinement. By the

• or Prussian blue nano-arrays. Complementary, quantum chemical calculations have addressed lanthanide complexes and metal-organic frameworks. This Thematic Series is part of a subsession of the same title, which took place at the E-MRS spring meeting in May 2014 in Lille, France. I would like to

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

• Shanka Walia and
• Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

• using different contrast agents (CAs). The ideal CA should be stable, tissue specific, less toxic with longer shelf life and a reasonable clearing period. The most common MRI CAs are paramagnetic chelated lanthanide complexes (positive contrast, T1-enhanced) and superparamagnetic iron oxide NPs

• (negative contrast, modified T2). Similarly the fluorescent CAs includes different lanthanide complexes, rare earth oxides, organic dyes, QDs, and ruthenium complexes. In this review article, we summarize recent literature reports on multifunctional nanocomposites for MRI and fluorescence imaging that are

• chemically modified with different targeting agents for a specific delivery of these nanocomposites. 2.1 Lanthanide complexes as both magnetic and fluorescent probe The electronic and magnetic properties of the lanthanide complexes are governed by 4f electrons. In some of the lanthanide complexes, the

Synthesis, characterization, monolayer assembly and 2D lanthanide coordination of a linear terphenyl-di(propiolonitrile) linker on Ag(111)

• Zhi Chen,
• Svetlana Klyatskaya,
• José I. Urgel,
• David Écija,
• Olaf Fuhr,
• Willi Auwärter,
• Johannes V. Barth and
• Mario Ruben

Beilstein J. Nanotechnol. 2015, 6, 327–335, doi:10.3762/bjnano.6.31

• single crystal X-ray diffraction analysis (XRD) along with other standard techniques (Supporting Information File 1). The results of the surface-confined, molecular self-assembly and the lanthanide coordination reaction were analysed by using low-temperature scanning tunnelling microscopy (STM). The STM

• investigation of the self-assembly of the organic linker 2 on a Ag(111) surface revealed a densely packed, chevron monolayer exhibiting a Moiré pattern. In contrast, lanthanide coordination of the same ligand 2 with Gd atoms resulted in metal–organic networks with only local order. These latter results differ

• gas phase, we obtained an average length of about 0.26 ± 04 nm for the phenylene–N distance, which is slightly shorter than in the earlier reported network of molecule 1 (0.33 ± 03 nm) [43]. Lanthanide-directed coordination of 2 on Ag(111) In previous work, regular metallo–supramolecular nanomeshes

Overview about the localization of nanoparticles in tissue and cellular context by different imaging techniques

• Anja Ostrowski,
• Daniel Nordmeyer,
• Alexander Boreham,
• Cornelia Holzhausen,
• Lars Mundhenk,
• Christina Graf,
• Martina C. Meinke,
• Annika Vogt,
• Sabrina Hadam,
• Jürgen Lademann,
• Eckart Rühl,
• Ulrike Alexiev and
• Achim D. Gruber

Beilstein J. Nanotechnol. 2015, 6, 263–280, doi:10.3762/bjnano.6.25

• undergo photobleaching, photoactivation is a remarkable property of QD enhancing their quantum yield over time [90]. Another group of highly photostable NP are lanthanide-doped upconversion NP (UCNP). Upconversion is an optical process in which the sequential absorption of two or more photons leads to the

Influence of the supramolecular architecture on the magnetic properties of a Dy^III single-molecule magnet: an ab initio investigation

• Julie Jung,
• Olivier Cador,
• Kevin Bernot,
• Fabrice Pointillart,
• Javier Luzon and
• Boris Le Guennic

Beilstein J. Nanotechnol. 2014, 5, 2267–2274, doi:10.3762/bjnano.5.236

• extensively characterize the magnetic anisotropy of the molecules [9][10][35][36][37][38] and its evolution with ligand modifications [39][40][41]. These studies have been performed mainly on lanthanide-based SMMs as these ions are expected to be extremely sensitive to modifications of the surrounding [42][43

• ]. The first strong experimental evidence has been given by the investigation of DyDOTA (where H4DOTA = 1,4,7,10-tetraazacyclododecane N,N′,N′′,N′′′-tetraacetic acid) the Dy derivative of the famous GdDOTA that is a commercial contrast agent used in MRI [44]. In this molecule, lanthanide coordination is

UHV deposition and characterization of a mononuclear iron(III) β-diketonate complex on Au(111)

• Irene Cimatti,
• Silviya Ninova,
• Valeria Lanzilotto,
• Luigi Malavolti,
• Luca Rigamonti,
• Brunetto Cortigiani,
• Matteo Mannini,
• Elena Magnano,
• Federica Bondino,
• Federico Totti,
• Andrea Cornia and
• Roberta Sessoli

Beilstein J. Nanotechnol. 2014, 5, 2139–2148, doi:10.3762/bjnano.5.223

• lanthanide or transition-metal ions, which are better suited for vapour-phase processing, in particular when β-diketonate ligands are present [11]. This work exploits the high volatility of the iron(III) tris-β-diketonate complex, Fe(dpm)3 (Hdpm = dipivaloylmethane), in order to perform a detailed in situ

Biocompatibility of cerium dioxide and silicon dioxide nanoparticles with endothelial cells

• Claudia Strobel,
• Martin Förster and
• Ingrid Hilger

Beilstein J. Nanotechnol. 2014, 5, 1795–1807, doi:10.3762/bjnano.5.190

• relevant cerium dioxide (CeO2) and silicon dioxide (SiO2) nanoparticles. CeO2, a rare-earth lanthanide element oxide, is mainly used in slurries for silicon wafer planarization [1][2], as automotive fuel additives to improve the efficiency of combustion [3][4], and as automobile catalytic converters [5

Spin relaxation in antiferromagnetic Fe–Fe dimers slowed down by anisotropic Dy^III ions

• Valeriu Mereacre,
• Frederik Klöwer,
• Yanhua Lan,
• Rodolphe Clérac,
• Juliusz A. Wolny,
• Volker Schünemann,
• Christopher E. Anson and
• Annie K. Powell

Beilstein J. Nanotechnol. 2013, 4, 807–814, doi:10.3762/bjnano.4.92

• ” the hyperfine field that is experienced by the iron nuclei. This has resulted in magnetic spectra with internal hyperfine fields of the iron nuclei of about 23 T. The set of data permitted us to conclude that the direction of the anisotropy in lanthanide nanosize molecular clusters is associated with

• huge Ising-type magnetic anisotropy of many lanthanide ions, which can be controlled by designing the ligand field, can slow down the relaxation of magnetisation and can be an effective source for the modulation of properties of transition metal molecular magnets [1]. The anisotropy of the lanthanide

• is severely affected by the symmetry of the crystal field and it can be controlled by a suitable design of the ligand field environment [2][3]. Today, the orientation of the principal axes of the magnetization of the lanthanide ions in low-symmetry environments can be determined theoretically and

Novel acridone-modified MCM-41 type silica: Synthesis, characterization and fluorescence tuning

• Maximilian Hemgesberg,
• Gunder Dörr,
• Yvonne Schmitt,
• Andreas Seifert,
• Zhou Zhou,
• Robin Klupp Taylor,
• Sarah Bay,
• Stefan Ernst,
• Markus Gerhards,
• Thomas J. J. Müller and
• Werner R. Thiel

Beilstein J. Nanotechnol. 2011, 2, 284–292, doi:10.3762/bjnano.2.33

• determination of lanthanide salts in aqueous solution, the fluorescence undergoing a bathochromic shift directly correlated to the acidity of the cation bound to its carbonyl group [8]. We therefore sought to create a micro- or mesoporous material containing covalently bound acridone units that would serve the