scholarly journals The Utility of 2,2′-Bipyrimidine in Lanthanide Chemistry: From Materials Synthesis to Structural and Physical Properties

2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Gaël Zucchi

This paper reviews the recent investigations undertaken on the use of 2,2′-bipyrimidine (bpm) as a ligand for designing molecular complexes as well as polymeric lanthanide materials. A special emphasis is put on the ability of this polydentate neutral ligand to yield compounds of various dimensionalities, to act as a connector between these large ions, and influence their emissive and magnetic properties. This ligand can adopt a terminal or a bridging coordination mode with lanthanide ions, thus generating a wealth of frameworks of various topologies with the 4f elements. The main focus of this review is to show the originality brought by bpm in lanthanide structural chemistry and solid-state photophysics and magnetism.

2014 ◽  
Vol 70 (a1) ◽  
pp. C1231-C1231
Author(s):  
Stuart Batten

We have synthesised large (2.7 nm) spherical metallosupramolecules (`nanoballs') with interesting properties [1-3]. Metal ions can be varied with retention of overall structure and crystal packing. The molecular packing creates cavities within the solid state, and the crystals readily absorb solvents such as methanol, acetonitrile or acetone (which also changes the magnetic properties), and absorb significant amounts of hydrogen and carbon dioxide (but not methane), pointing to a new class of porous materials. Other properties include switching between two magnetic spin states (spin crossover) upon change in temperature or irradiation of light, and size-selective catalysis. New packing arrangements of the nanoballs can then be achieved through variation of the counteranions or nitrile solvent, leading to new phases with different physical properties.


1993 ◽  
Vol 329 ◽  
Author(s):  
Michael Canva ◽  
Patrick Georges ◽  
Jean-Fran^ois Perelgritz ◽  
Alain Brun ◽  
Fréddric Chaput ◽  
...  

AbstractPhotoresistant laser dyes were trapped in silica based xerogel host matrices to obtain solid state tunable lasers. For this purpose very dense xerogel samples with improved chemical and physical properties were prepared at room temperature by the sol-gel technology. The as-prepared materials were polished to obtain optical quality surfaces and were used as new lasing media.Lasing action of such different dyes as rhodamine, perylene and pyrromethene doping dense sol-gel matrices was demonstrated. Efficiencies of 30 % or lifetimes of more than 100,000 shots were achieved with different new ≤dye dopant/host matrix≥ couples. Their different performances are reviewed and discussed.


2020 ◽  
Author(s):  
Xiaojing Xia ◽  
Anupum Pant ◽  
Xuezhe Zhou ◽  
Elena Dobretsova ◽  
Alex Bard ◽  
...  

Fluoride crystals, due to their low phonon energies, are attractive hosts of trivalent lanthanide ions for applications in upconverting phosphors, quantum information science, and solid-state laser refrigeration. In this article, we report the rapid, low-cost hydrothermal synthesis of potassium lutetium fluoride (KLF) microcrystals for applications in solid-state laser refrigeration. Four crystalline phases were synthesized, namely orthorhombic K<sub>2</sub>LuF<sub>5</sub> (Pnma), trigonal KLuF<sub>4</sub> (P3<sub>1</sub>21), orthorhombic KLu<sub>2</sub>F<sub>7</sub> (Pna2<sub>1</sub>), and cubic KLu<sub>3</sub>F<sub>10</sub> (Fm3m), with each phase exhibiting unique microcrystalline morphologies. Luminescence spectra and emission lifetimes of the four crystalline phases were characterized based on the point-group symmetry of trivalent cations. Laser refrigeration was measured by observing both the optomechanical eigenfrequencies of microcrystals on cantilevers in vacuum, and also the Brownian dynamics of optically trapped microcrystals in water. Among all four crystalline phases, the most significant cooling was observed for 10%Yb:KLuF<sub>4</sub> with cooling of 8.6 $\pm$ 2.1 K below room temperature. Reduced heating was observed with 10%Yb:K<sub>2</sub>LuF<sub>5</sub>


Alloy Digest ◽  
1999 ◽  
Vol 48 (1) ◽  

Abstract Armco DI-MAX nonoriented electrical steels have practically identical magnetic properties in any direction of magnetism in the plane of the material. They have superior permeability at high inductions, low average core loss, good gage uniformity, excellent flatness, and a high stacking factor. This datasheet provides information on composition, physical properties, hardness, and tensile properties. Filing Code: FE-88. Producer or source: Armco Inc., Specialty Steels Division. Originally published April 1989, revised January 1999.


2021 ◽  
Author(s):  
Stanislav N. Melnikov ◽  
Igor Evstifeev ◽  
Stanislav A. Nikolaevskii ◽  
Ivan V. Ananyev ◽  
Evgenia Varaksina ◽  
...  

The systematical series of Zn-Ln trinuclear carboxylate molecular complexes with general formula [Zn2Ln(NO3)(phbz)6(L)2] (Ln = Eu, Gd, Tb; phbz is anion of 4-biphenylcarboxylic acid; L is pyridine, 2,3-lutidine or 2,2’-bipyridine)...


Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 378
Author(s):  
Li Zhao ◽  
Zhiwei Hu ◽  
Hanjie Guo ◽  
Christoph Geibel ◽  
Hong-Ji Lin ◽  
...  

We report on the synthesis and physical properties of cm-sized CoGeO3 single crystals grown in a high pressure mirror furnace at pressures of 80 bar. Direction dependent magnetic susceptibility measurements on our single crystals reveal highly anisotropic magnetic properties that we attribute to the impact of strong single ion anisotropy appearing in this system with TN∼33.5 K. Furthermore, we observe effective magnetic moments that are exceeding the spin only values of the Co ions, which reveals the presence of sizable orbital moments in CoGeO3.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3393
Author(s):  
Mikhail A. Vershinin ◽  
Marianna I. Rakhmanova ◽  
Alexander S. Novikov ◽  
Maxim N. Sokolov ◽  
Sergey A. Adonin

Reactions between Zn(II) dihalides and 2-halogen-substituted pyridines 2-XPy result in a series of heteroleptic molecular complexes [(2-XPy)2ZnY2] (Y = Cl, X = Cl (1), Br (2), I (3); Y = Br, X = Cl (4), Br (5), I (6), Y = I, X = Cl (7), Br (8), and I (9)). Moreover, 1–7 are isostructural (triclinic), while 8 and 9 are monoclinic. In all cases, halogen bonding plays an important role in formation of crystal packing. Moreover, 1–9 demonstrate luminescence in asolid state; for the best emitting complexes, quantum yield (QY) exceeds 21%.


Nanoscale ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 4519-4529
Author(s):  
J. Mohapatra ◽  
J. Elkins ◽  
M. Xing ◽  
D. Guragain ◽  
Sanjay R. Mishra ◽  
...  

Self-assembly of nanoparticles into ordered patterns is a novel approach to build up new consolidated materials with desired collective physical properties.


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