Modified Born-Lande equation to calculate the lattice energy: A theoretical treatise

2021 ◽  
Author(s):  
Aakash Gupta
Keyword(s):  
Lattice Energy

On the reliability of volume-based thermodynamics for inorganic-organic salts and coordination compounds with uncharged ligands

2017 ◽  
Author(s):  
Robson de Farias
Keyword(s):  
Coordination Compound ◽  
Coordination Compounds ◽  
Formation Enthalpy ◽  
Lattice Energy ◽  
Chemical Hardness ◽  
Acid Anion ◽  
Organic Salts ◽  
Density Values ◽  
Lattice Energies

In the present work, the reliability of the volume-based thermodynamics (VBT) methods in the calculation of lattice energies is investigated by applying the “traditional” Kapustinskii equation [8], as well as Glasser-Jenkins [3] and Kaya [5] equations to calculate the lattice energies for Na, K and Rb pyruvates [9-11] as well as for the coordination compound [Bi(C<sub>7</sub>H<sub>5</sub>O<sub>3</sub>)<sub>3</sub>C<sub>12</sub>H<sub>8</sub>N<sub>2</sub>] [17] (in which C<sub>12</sub>H<sub>8</sub>N<sub>2</sub> = 1,10 phenathroline and C<sub>7</sub>H<sub>5</sub>O<sub>3</sub><sup>-</sup>= <i>o</i>-hyddroxybenzoic acid anion). As comparison, the lattice energies are also calculated using formation enthalpy values for sodium pyrivate and [Bi(C<sub>7</sub>H<sub>5</sub>O<sub>3</sub>)<sub>3</sub>C<sub>12</sub>H<sub>8</sub>N<sub>2</sub>]. For the pyruvates, is verified that none of the considered approach, Kapustinskii, Glasser, Kaya or density, provides values that agrees in an acceptable % difference, with the lattice energy values calculated from the formation enthalpy values. However, it must be pointed out that Kaya approach, with deals with a chemical hardness approach is the better one for such kind of inorganic-organic salts. Based on data obtained for [Bi(C<sub>7</sub>H<sub>5</sub>O<sub>3</sub>)<sub>3</sub>C<sub>12</sub>H<sub>8</sub>N<sub>2</sub>] is concluded that the only one VBT method that provides reliable lattice energies for compounds with bulky uncharged ligands is that one based on density values (derived by Glasser-Jenkins).

Electron microscopy investigations on the mineral lorándite (TlAsS2) from Allchar in Macedonia

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Tobias Necke ◽  
Maximilian Trapp ◽  
Stefan Lauterbach ◽  
Georg Amthauer ◽  
Hans-Joachim Kleebe
Keyword(s):  
Electron Microscopy ◽  
Single Crystals ◽  
Secondary Phase ◽  
Lattice Energy ◽  
Local Deformation ◽  
Crystal Defects ◽  
Coffee Bean ◽  
Electron Dose ◽  
Chemical Difference ◽  
Natural Mineral

Abstract In this paper, we report on electron microscopy studies of single crystals of the natural mineral lorándite, TlAsS2. The main focus of this investigation was to address the question as to whether those lorándite crystals are chemically and structurally homogeneous, in order to be utilized as an effective neutrino detector within the lorándite experiment (LOREX) project. Apart from few secondary minerals, being present only at the surface of the lorándite samples, scanning electron microscopy (SEM) indicated homogeneous crystals. Similarly, transmission electron microscopy (TEM) imaging revealed a homogenous and undisturbed crystal structure, with the only exception of local coffee-bean contrasts; however, rarely observed. These specific contrast variations are known to be a typical strain indicator caused by a local deformation of the crystal lattice. Energy-dispersive X-ray spectroscopy (EDS) in conjunction with electron energy-loss spectroscopy (EELS) did not show any significant chemical difference when analysing regions on or off those coffee-bean features, indicating a chemically homogenous mineral. Since the presence of lattice disturbing secondary phase precipitates could be excluded by imaging and complementary chemical analysis, crystal defects such as dislocations and stacking faults or minor fluid inclusions are discussed as the probable origin of this local elastic strain. The experimental results confirm that the studied lorándite single crystals fulfil all structural and chemical requirements to be employed as the natural mineral that allows to determine solar neutrino fluxes. In addition, critical issues regarding the rather challenging sample preparation of lorándite are reported and a quantification of the maximum tolerable electron dose in the TEM is presented, since lorándite was found to be sensitive with respect to electron beam irradiation. Furthermore, the limits of EDS measurements due to peak overlapping are shown and discussed utilizing the case of Pb in lorándite. In this regard, a comparison with the Tl- and Pb-containing natural mineral hutchinsonite, TlPbAs5S9, is also included.

scholarly journals Sintering behaviour, lattice energy and microwave dielectric properties of melilite-type BaCo2Si2O7 ceramics

2020 ◽  
Vol 6 (12) ◽  
pp. 126322 ◽  
Author(s):  
Xiao-Qiang Song ◽  
Wen Lei ◽  
Meng-Qi Xie ◽  
Jie Li ◽  
Xiao-Chuan Wang ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Microwave Dielectric Properties ◽  
Lattice Energy ◽  
Microwave Dielectric ◽  
Sintering Behaviour

Crystal structure and lattice energetics of 10-methylacridinium halides

2000 ◽  
Vol 53 (8) ◽  
pp. 627 ◽  
Author(s):  
Piotr Storoniak ◽  
Karol Krzyminski ◽  
Pawel Dokurno ◽  
Antoni Konitz ◽  
Jerzy Blazejowski
Keyword(s):  
Crystal Lattice ◽  
Lattice Energy ◽  
Enthalpies Of Formation ◽  
Triclinic Space Group ◽  
X Ray ◽  
Molecular Arrangement ◽  
Van Der Waals Contacts ◽  
Chloride Monohydrate ◽  
Insight Into

The crystal structures of 10-methylacridinium chloride monohydrate, bromide monohydrate and iodide were determined by X-ray analysis. The compounds crystallize in the triclinic space group, P¯1, with 2 molecules in the unit cell. The molecular arrangement in the crystals revealed that hydrogen bonds (in hydrates) and van der Waals contacts play a significant part in intermolecular interactions. To discover their nature, contributions to the crystal lattice energy arising from electrostatic (the most important since the compounds form ionic crystals), dispersive and repulsive interactions were calculated. Enthalpies of formation of the salts, their stability and susceptibility to decomposition could be predicted from a combination of crystal lattice energies with values of other thermochemical characteristics obtained theoretically or taken from the literature. The role of water in the stabilization of the crystal lattice of the hydrates is also explained. The information gathered has given an insight into the features and behaviour of compounds which can be regarded as models of a large group of aromatic quaternary nitrogen salts.

scholarly journals Blind crystal structure prediction of a novel second polymorph of 1-hydroxy-7-azabenzotriazole

2006 ◽  
Vol 62 (4) ◽  
pp. 642-650 ◽  
Author(s):  
Harriott Nowell ◽  
Christopher S. Frampton ◽  
Julie Waite ◽  
Sarah L. Price
Keyword(s):  
Crystal Structure ◽  
Structure Prediction ◽  
Structure Refinement ◽  
Lattice Energy ◽  
Polymorphic Form ◽  
Crystal Structure Prediction ◽  
Blind Test ◽  
Coupling Reagent ◽  
Energy Penalty ◽  
Alcohol Solvents

The commercially available peptide coupling reagent 1-hydroxy-7-azabenzotriazole has been shown to crystallize in two polymorphic forms. The two polymorphs differ in their hydrogen-bonding motif, with form I having an R_2^2(10) dimer motif and form II having a C(5) chain motif. The previously unreported form II was used as an informal blind test of computational crystal structure prediction for flexible molecules. The crystal structure of form II has been successfully predicted blind from lattice-energy minimization calculations following a series of searches using a large number of rigid conformers. The structure for form II was the third lowest in energy with form I found as the global minimum, with the energy calculated as the sum of the ab initio intramolecular energy penalty for conformational distortion and the intermolecular lattice energy which is calculated from a distributed multipole representation of the charge density. The predicted structure was sufficiently close to the experimental structure that it could be used as a starting model for crystal structure refinement. A subsequent limited polymorph screen failed to yield a third polymorphic form, but demonstrated that alcohol solvents are implicated in the formation of the form I dimer structure.

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