A first exploration of isostructurality in transition metal nitroprussides: X-ray analysis, magnetic properties and DFT calculations

CrystEngComm ◽  
2020 ◽  
Author(s):  
Hiram Pérez ◽  
Alejandro Di Santo ◽  
Oscar E. Piro ◽  
Gustavo A. Echeverría ◽  
A. Cano ◽  
...  

Transition metal M(ii) (M = Mn, Fe, Cu, Zn, Cd) nitroprussides with 1-methyl-imidazole were prepared and characterized by spectroscopic techniques, thermal analysis, and powder (Fe complex) and single-crystal XRD.

1977 ◽  
Vol 32 (7) ◽  
pp. 783-784 ◽  
Author(s):  
D. W. Engelfriet ◽  
J. G. Haasnoot ◽  
W. L. Groeneveld

Abstract The magnetic susceptibilities of some transition metal (II) complexes with 1,2,4-triazole (trz) have been measured in the range 2-300 K. Ni (trz)2 (NO3)2 (H2O) 8/3, Ni (trz)2 SO4 (H2O)5 and α-Ni (trz)2 (NCS)2 are found to be linear antiferromagnetic trimers. For β- Ni (trz)2 (NCS)2 and similar compounds with Mn (II), Fe (II), Co (II) and Cu(II), totally different magnetic properties were observed, suggesting the presence of two-dimensional networks of metal ions bridged by 1,2,4-triazole molecules. For Co (trz) 2 (NCS) 2 this was confirmed by X-ray single crystal diffraction.


2020 ◽  
Vol 85 (10) ◽  
pp. 1279-1290
Author(s):  
Tanja Keskic ◽  
Dusanka Radanovic ◽  
Andrej Pevec ◽  
Iztok Turel ◽  
Maja Gruden ◽  
...  

Abstract: Binuclear double end-on azido bridged Ni(II) complex (1) with composition [Ni2L2(?-1,1-N3)2(N3)2]?6H2O, (L = (E)-N,N,N-trimethyl-2-oxo-2-(2- -(1-(pyridin-2-yl)ethylidene)hydrazinyl)ethan-1-amin) was synthesized and characterized by single-crystal X-ray diffraction method. Ni(II) ions are hexacoordinated with the tridentate heteroaromatic hydrazone-based ligand and three azido ligands (one terminal and two are end-on bridges). DFT calculations revealed that coupling between two Ni(II) centers is ferromagnetic in agreement with binuclear Ni(II) complexes with similar structures.


Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 272
Author(s):  
Seungyeol Lee ◽  
Huifang Xu ◽  
Hongwu Xu ◽  
Joerg Neuefeind

The crystal structure of moganite from the Mogán formation on Gran Canaria has been re-investigated using high-resolution synchrotron X-ray diffraction (XRD) and X-ray/neutron pair distribution function (PDF) analyses. Our study for the first time reports the anisotropic atomic displacement parameters (ADPs) of a natural moganite. Rietveld analysis of synchrotron XRD data determined the crystal structure of moganite with the space group I2/a. The refined unit-cell parameters are a = 8.7363(8), b = 4.8688(5), c = 10.7203(9) Å, and β = 90.212(4)°. The ADPs of Si and O in moganite were obtained from X-ray and neutron PDF analyses. The shapes and orientations of the anisotropic ellipsoids determined from X-ray and neutron measurements are similar. The anisotropic ellipsoids for O extend along planes perpendicular to the Si-Si axis of corner-sharing SiO4 tetrahedra, suggesting precession-like movement. Neutron PDF result confirms the occurrence of OH over some of the tetrahedral sites. We postulate that moganite nanomineral is stable with respect to quartz in hypersaline water. The ADPs of moganite show a similar trend as those of quartz determined by single-crystal XRD. In short, the combined methods can provide high-quality structural parameters of moganite nanomineral, including its ADPs and extra OH position at the surface. This approach can be used as an alternative means for solving the structures of crystals that are not large enough for single-crystal XRD measurements, such as fine-grained and nanocrystalline minerals formed in various geological environments.


1999 ◽  
Vol 23 (7) ◽  
pp. 418-419
Author(s):  
Simon J. Coles ◽  
Paul Faulds ◽  
Michael B. Hursthouse ◽  
David G. Kelly ◽  
Georgia C. Ranger ◽  
...  

Nickel(II) phosphine complexes are prepared with a series of diphenylalkenylphosphine ligands and characterised by single crystal X-ray diffraction and spectroscopic techniques.


Author(s):  
Ahmet Karadag ◽  
Hümeyra Pasaoglu ◽  
Gökhan Kastas ◽  
Orhan Büyükgüngör

AbstractThe cyano-bridged heteronuclear coordination polymer of zinc(II)/nickel(II) has been prepared by N-(2-hydroxyethyl)-ethylendiamine (hydet-en), alternatively named 2-(2-aminoethylamino)-ethanol and characterised by IR and thermal analysis. In the bimetallic complex, the decomposition of hydet-en ligands is seen to be endothermic whereas that of the cyano ligands is found to be exothermic. The crystal structure of the complex has been determined by single-crystal X-ray diffraction. The crystal structure of the zinc(II)-nickel(II) complex consists of a one-dimensional polymeric chain –Zn(hydet-en)


Author(s):  
Marieta Muresan-Pop ◽  
Sergiu Macavei ◽  
Alexandru Turza ◽  
Gheorghe Borodi

Four new solvates of the anti-HIV compound etravirine [systematic name: 4-({6-amino-5-bromo-2-[(4-cyanophenyl)amino]pyrimidin-4-yl}oxy)-3,5-dimethylbenzonitrile, C20H15BrN6O] with dimethyl sulfoxide (C2H6OS, two distinct monosolvates), 1,4-dioxane (C4H8O2, the 0.75-solvate) and N,N-dimethylacetamide (C4H9NO, the monosolvate), which exhibit conversion to the same anhydrous etravirine phase upon desolvation, and a stable etravirinium oxalate salt {6-amino-5-bromo-4-(4-cyano-2,6-dimethylphenoxy)-2-[(4-cyanophenyl)amino]pyrimidin-1-ium hemioxalate, C20H16BrN6O+·0.5C2O4 2−} were obtained. The crystal structures were solved by single-crystal X-ray diffraction and analyzed by powder X-ray diffraction, and the intermolecular interactions were explored by Hirshfeld surface analysis. Lattice energies were evaluated using the atom–atom force field Coulomb–London–Pauli (AA CLP) approximation, which distributes the total energy as four separate contributions: Coulombic, polarization, dispersion and repulsion. The formation of the solvates and the oxalate salt was further characterized by thermal analysis and IR spectroscopy.


2004 ◽  
Vol 848 ◽  
Author(s):  
Evan Lyle Thomas ◽  
Erin E. Erickson ◽  
Monica Moldovan ◽  
David P. Young ◽  
Julia Y. Chan

AbstractA new member of the LnMIn5 family, ErCoIn5, has been synthesized by a flux-growth method. The structure of ErCoIn5 was determined by single crystal X-ray diffraction. It crystallizes in the tetragonal space group P4/mmm, Z = 1, with lattice parameters a = 4.5400(4) and c = 7.3970(7) Å, and V = 152.46(2) Å3. Electrical resistivity data show metallic behavior. Magnetic susceptibility measurements show this compound to be antiferromagnetic with TN = 5.1 K. We compare these experimental results with those of LaCoIn5 in an effort to better understand the effect of the structural trends observed on the transport and magnetic properties.


Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1934 ◽  
Author(s):  
Jing Xu ◽  
Haiying Wang ◽  
Zhongpo Zhou ◽  
Zhaorui Zou

In this work, undoped, N-doped, WO3-loaded undoped, and WO3-loaded with N-doped TiO2 rutile single-crystal wafers were fabricated by direct current (DC) magnetron sputtering. N-doping into TiO2 and WO3 loading onto TiO2 surface were used to increase and decrease oxygen vacancies. Various measurements were conducted to analyze the structural and magnetic properties of the samples. X-ray diffraction results showed that the N-doping and WO3 loading did not change the phase of all samples. X-ray photoelectron spectroscopy results revealed that W element loaded onto rutile single-crystal wafers existed in the form of WO3. UV-Vis spectrometer results showed that the absorption edge of WO3-loaded undoped and WO3-loaded with N-doped TiO2 rutile single-crystal wafers had red shift, resulting in a slight decrease in the corresponding band gap. Photoluminescence spectra indicated that oxygen vacancies existed in all samples due to the postannealing atmosphere, and oxygen vacancies density increased with N-doping, while decreasing with WO3 loading onto TiO2 surface. The magnetic properties of the samples were investigated, and the saturation magnetization values were in the order N-doped > WO3-loaded with N-doped > undoped > WO3-loaded undoped rutile single-crystal wafers, which was the same order as the oxygen vacancy densities of these samples. N-doping improved the saturation magnetization values, while WO3-loaded decreased the saturation magnetization values. This paper reveals that the magnetic properties of WO3-loaded with N-doped rutile single-crystal wafers originate from oxygen vacancies.


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