A5047458591- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Magnetism in coordination complexes
- Lanthanide and Transition Metal Complexes
- Metal-Catalyzed Oxygenation Mechanisms
- Metal-Organic Frameworks: Synthesis and Applications
- Molecular Junctions and Nanostructures
- Advanced NMR Techniques and Applications
- Crystallography and molecular interactions
- Supramolecular Chemistry and Complexes
- Nanocluster Synthesis and Applications
- Porphyrin and Phthalocyanine Chemistry
- Alzheimer's disease research and treatments
- Metal complexes synthesis and properties
- Electrochemical Analysis and Applications
- Mass Spectrometry Techniques and Applications
- Iron Metabolism and Disorders
- Advanced biosensing and bioanalysis techniques
- Graphene research and applications
- Molecular Sensors and Ion Detection
- Surface Chemistry and Catalysis
- Supramolecular Self-Assembly in Materials
- Fullerene Chemistry and Applications
- Free Radicals and Antioxidants
- Electron Spin Resonance Studies
University of Chile
2012-2024
University of Florida
2002-2020
Instituto de Biotecnología y Biología Molecular
2018-2019
Institute of Mathematical Sciences
2016-2019
Handan College
2017
University of Akron
2009-2010
Michigan State University
2008
Centre National de la Recherche Scientifique
2003-2005
University of Bern
2005
University of Manchester
2004-2005
The largest single-molecule magnet (SMM) to date has been prepared and studied. Recrystallization of known [Mn12O12(O2CCH2But)16(H2O)4] (1; 8MnIII, 4MnIV) from CH2Cl2/MeNO2 causes its conversion [Mn30O24(OH)8(O2CCH2But)32(H2O)2(MeNO2)4] (2; 3MnII, 26MnIII, MnIV). structure 2 consists a central, near-linear [Mn4O6] backbone, either side which are attached two [Mn13O9(OH)4] units. Peripheral ligation around the resulting [Mn30O24(OH)8] core is by 32 ButCH2CO2-, H2O, 4 MeNO2 groups. molecule...
The reaction of the mixed-valent metal triangles [Mn(3)O(O(2)CR)(6)(py)(3)] (R = CH(3), Ph, C(CH(3))(3)) with tripodal ligands H(3)thme (1,1,1-tris(hydroxymethyl)ethane) and H(3)tmp (1,1,1-tris(hydroxymethyl)propane) in MeCN, produces a family manganese rodlike complexes whose structures are all derived from series edge-sharing triangles. Variable temperature direct current (dc) magnetic susceptibility data were collected for 1.8-300 K range fields up to 7.0 T. Complex 1,...
Self-assembly of 1,3-di(4'-terpyridinyl)arenes by using the labile tpy-Cd(II)-tpy (where tpy = 2,2':6',2''-terpyridine) connectivity afforded access to hexacadmium macrocycles in high yield. These supramolecular assemblies were characterized traveling wave ion mobility mass spectrometry (TWIM-MS).
The complex [Mn(12)O(12)(O(2)CCHCl(2))(16)(H(2)O)(4)] (2) in MeCN exhibits three quasi-reversible one-electron reduction processes at significantly higher potentials than [Mn(12)O(12)(O(2)CMe)(16)(H(2)O)(4)] (1). This has allowed the two-electron reduced version of 2 to be generated and isolated. Reaction with one two equivalents PPh(4)I led isolation (PPh(4))[Mn(12)O(12)(O(2)CCHCl(2))(16)(H(2)O)(4)] (3) (PPh(4))(2)[Mn(12)O(12)(O(2)CCHCl(2))(16)(H(2)O)(4)] (4), respectively. latter...
Methods are reported for the preparation of mixed-carboxylate versions [Mn(12)O(12)(O(2)CR)(16)(H(2)O)(4)] family single-molecule magnets (SMMs). [Mn(12)O(12)(O(2)CCHCl(2))(8)(O(2)CCH(2)Bu(t))(8)(H(2)O)(3)] (5) and [Mn(12)O(12)(O(2)CHCl(2))(8)(O(2)CEt)(8)(H(2)O)(3)] (6) have been obtained from 1:1 reaction corresponding homocarboxylate species. Complex 5.CH(2)Cl(2).H(2)O crystallizes in triclinic space group P1 with, at -165 degrees C, a = 15.762(1), b 16.246(1), c 23.822(1) A, alpha...
Magnetization measurements of molecular clusters [Mn12]2− with a spin ground state S=10 show resonance tunneling at avoided energy level crossings. The observed oscillations the tunnel probability as function magnetic field applied along hard anisotropy axis are due to topological quantum phase interference two paths opposite windings. is therefore second cluster exhibiting interference.
The reaction of [Mn(3)O(O(2)CMe)(6)(py)(3)] with the tripodal ligand H(3)thme (1,1,1-tris(hydroxymethyl)ethane) affords enneanuclear complex [Mn(9)O(7)(O(2)CCH(3))(11)(thme)(py)(3)(H(2)O)(2)] 1.1MeCN.1Et(2)O. metallic skeleton 1 comprises a series 10 edge-sharing triangles that describes part an idealized icosahedron. Variable temperature direct current (dc) magnetic susceptibility data collected in 1.8-300 K range and fields up to 5.5 T were fitted give spin ground state S = (17)/(2) axial...
TWIM peaks: A macrocycle containing 12 PdII terpyridyl centers was assembled using 4,4′-bipyridyl ligands and characterized by NMR traveling wave ion mobility mass spectrometry (TWIM-MS). The macrocyclic architecture also examined tandem collisionally activated dissociation (CAD) experiments (see picture; C gray, N blue, Pd orange), the resulting fragments were monitored time-of-flight analysis. Detailed facts of importance to specialist readers are published as "Supporting Information"....
The origin of the second, faster relaxation process in Mn12 molecules has been identified as a different relative orientation Jahn–Teller elongation axes MnIII ions, which we have termed 'Jahn–Teller isomerism'.
The reaction of [Mn3O(OAc)6(py)3] with 1,1,1-tris(hydroxymethyl)ethane (H3thme) gives the Mn(IV)3Mn(III)4Mn(II)2 complex [Mn9O7(OAc)11(thme)(py)3(H2O)2], which has an S = 17/2 ground state and displays strong out-of-phase signals in ac susceptibility studies that establish it as a new class single-molecule magnet.
Dianionic members of the Mn12 family single-molecule magnets have been prepared by two-electron reduction neutral cluster; [PPh4]2[Mn12O12(O2C CHCl2)16- (H2O)4] representative has shown to possess an S = 10 ground state and exhibit out-of-phase ac susceptibility signals diagnostic magnetism behavior.
The syntheses, crystal structures, and magnetic properties of [Mn(12)O(12)(O(2)CC(6)F(5))(16)(H(2)O)(4)] (2), (NMe(4))[Mn(12)O(12)(O(2)CC(6)F(5))(16)(H(2)O)(4)] (3), (NMe(4))(2)[Mn(12)O(12)(O(2)CC(6)F(5))(16)(H(2)O)(4)] (4) are reported. Complex 2 displays quasi-reversible redox couples when examined by cyclic voltammetry in CH(2)Cl(2): one-electron reductions observed at 0.64 0.30 V vs ferrocene. reaction complex with 1 equiv NMe(4)I yields the one- two-electron reduced analogues, 3 4,...
Pentamer—the black sheep in the family! FeII-mediated complexation of acetyl-protected, carbohydrate-functionalized 3,5-di(2,2′:6′,2′′-terpyridinyl)arenes possessing a 120° angle between two terpyridines afforded predesigned hexamer and unexpected pentamer (see scheme); both formed self-assembled nanofibers.
The early detection of the amyloid beta peptide aggregates involved in Alzheimer’s disease is crucial to test new potential treatments. In this research, we improved vitro and ex vivo by fluorescence combining use CRANAD-2 gold nanorods (GNRs) surface enhancement effect. We synthetized GNRs modified their with HS-PEG-OMe HS-PEG-COOH functionalized them D1 peptide, which has capability selectively bind peptide. For an co-incubated probe GNR-PEG-D1 observing increase intensity signal...
Faster- and slower-relaxing versions of the title Mn12 compound have been obtained in pure forms that crystallize same space group differ only identity one lattice solvent molecule; loss causes isomerization from faster- to form.
The reaction of the neutral triangle [Mn3O(O2CR)6(L)3] with 1,1,1-tris(hydroxymethyl)ethane (H3thme) affords novel dodecanuclear and octanuclear manganese complexes unusual ladder-like cores built from edge-sharing triangles.
The syntheses, physical, and photophysical properties of a family complexes having the general formula [M2(L)(mcb)(Ru(4,4'-(X)2-bpy)2)](PF6)3 (where M = MnII or ZnII, X CH3 CF3, mcb is 4'-methyl-4-carboxy-2,2'-bipyridine, L Schiff base macrocycle derived from 2,6-diformyl-4-methylphenol bis(2-aminoethyl)-N-methylamine) are described. isostructural molecules all consist dinuclear metal cores covalently linked to RuII polypyridyl complex. Photoexcitation [Mn2(L)(mcb)(Ru((CF3)2-bpy)2)](PF6)3...
The synthesis and characterization of a family [60]fullerocurcuminoids obtained via Bingel reactions is reported. new C60 derivatives include curcumin curcuminoids with variety end groups. Preliminary biological experiments show the potential activity compound containing addend, which exhibits moderate anti-HIV-1 radical scavenger properties, but no anti-cancer activity. In addition, fullerocurcuminoids exhibit HOMO/LUMO energy levels that are reasonably matched those perovskites when they...
We report inelastic neutron scattering (INS) studies on a series of Mn(12) derivatives, [Mn(12)O(12)(O2CC6F5)16(H2O)4]z, in which the number unpaired electrons cluster is varied. investigated three oxidation levels: z = 0 for neutral complex, -1 one-electron reduced species and -2 two-electron complex. For 0, ground state S 10 as prototypical Mn12-acetate. -1, we have 19/2, - 2, an retrieved. INS show that axial zero-field splitting parameter D strongly suppressed upon successive electron...
Switching of conductance between conformers can be explained by the rotation one methyl group.