Expanding the Supramolecular Toolkit: Computed Molecular and Crystal Properties for Supporting the Crystal Engineering of Higher-Order Molecular Ionic Cocrystals

The ability to rationally design and predictably construct crystalline solids has been the hallmark of crystal engineering research over the past two decades. When building higher-order multicomponent cocrystals (i.e. crystals containing more than two constituents), the differential and hierarchical way molecules interact and assemble in the solidstate is of pinnacle importance. To date, numerous examples of multicomponent crystals comprising organic molecules leading to salts, cocrystals or ionic cocrystals have been reported. However, the crystal engineering of hybrid organicinorganic cocrystals with sophisticated inorganic building blocks is still poorly understood and mostly unexplored. Here, we reveal the first efficient mechanochemical synthesis of higher-order hybrid organic-inorganic cocrystals based on the structurally versatile – yet largely unexplored – cyclodiphos(V/V)azane heterosynthon building block. The novel hybrid ternary and quaternary multicomponent cocrystals herein reported are held together by synergistic intermolecular interactions (e.g., hydrogen- and halogen-bonding, Se-π and ion-dipole interactions). Notably, higher-order ternary and quaternary cocrystals can be readily obtained either via direct synthetic routes from its individual components, or via unprecedented telescopic approaches from lower-order cocrystal sets. In addition, computational modelling has also revealed that the formation of higher-order cocrystals is thermodynamically driven, and that bulk moduli and compressibilities are strongly dependent on the chemical composition and intermolecular forces present in the crystals, which offer untapped potential for optimizing material properties.

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Direct and Telescopic Mechanochemical Synthesis of Higher-order Organic-Inorganic Hybrid Cocrystals: Tuning Order, Functionality and Size in Cocrystal Design

10.26434/chemrxiv.13515938 ◽

2021 ◽

Author(s):

Zi xuan Ng ◽

Davin Tan ◽

Wei Liang Teo ◽

felix leon ◽

Xiaoyan Shi ◽

...

Keyword(s):

Mechanochemical Synthesis ◽

Crystal Engineering ◽

Computational Modelling ◽

Halogen Bonding ◽

Building Blocks ◽

Intermolecular Forces ◽

Higher Order ◽

The Novel ◽

Engineering Research ◽

Dipole Interactions

The ability to rationally design and predictably construct crystalline solids has been the hallmark of crystal engineering research over the past two decades. When building higher-order multicomponent cocrystals (i.e. crystals containing more than two constituents), the differential and hierarchical way molecules interact and assemble in the solidstate is of pinnacle importance. To date, numerous examples of multicomponent crystals comprising organic molecules leading to salts, cocrystals or ionic cocrystals have been reported. However, the crystal engineering of hybrid organicinorganic cocrystals with sophisticated inorganic building blocks is still poorly understood and mostly unexplored. Here, we reveal the first efficient mechanochemical synthesis of higher-order hybrid organic-inorganic cocrystals based on the structurally versatile – yet largely unexplored – cyclodiphos(V/V)azane heterosynthon building block. The novel hybrid ternary and quaternary multicomponent cocrystals herein reported are held together by synergistic intermolecular interactions (e.g., hydrogen- and halogen-bonding, Se-π and ion-dipole interactions). Notably, higher-order ternary and quaternary cocrystals can be readily obtained either via direct synthetic routes from its individual components, or via unprecedented telescopic approaches from lower-order cocrystal sets. In addition, computational modelling has also revealed that the formation of higher-order cocrystals is thermodynamically driven, and that bulk moduli and compressibilities are strongly dependent on the chemical composition and intermolecular forces present in the crystals, which offer untapped potential for optimizing material properties.

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Intermolecular interactions in molecular crystals: what’s in a name?

Faraday Discussions ◽

10.1039/c7fd00072c ◽

2017 ◽

Vol 203 ◽

pp. 93-112 ◽

Cited By ~ 41

Author(s):

Alison J. Edwards ◽

Campbell F. Mackenzie ◽

Peter R. Spackman ◽

Dylan Jayatilaka ◽

Mark A. Spackman

Keyword(s):

Hydrogen Bonds ◽

Intermolecular Interactions ◽

Crystal Engineering ◽

Molecular Electrostatic Potential ◽

Molecular Crystals ◽

Interaction Energies ◽

Structure Property ◽

Structure Property Relationships ◽

Crystal Properties ◽

Tetrel Bonds

Structure–property relationships are the key to modern crystal engineering, and for molecular crystals this requires both a thorough understanding of intermolecular interactions, and the subsequent use of this to create solids with desired properties. There has been a rapid increase in publications aimed at furthering this understanding, especially the importance of non-canonical interactions such as halogen, chalcogen, pnicogen, and tetrel bonds. Here we show how all of these interactions – and hydrogen bonds – can be readily understood through their common origin in the redistribution of electron density that results from chemical bonding. This redistribution is directly linked to the molecular electrostatic potential, to qualitative concepts such as electrostatic complementarity, and to the calculation of quantitative intermolecular interaction energies. Visualization of these energies, along with their electrostatic and dispersion components, sheds light on the architecture of molecular crystals, in turn providing a link to actual crystal properties.

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Dual systems for all: Higher-order, role-based relational reasoning as a uniquely derived feature of human cognition

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000451 ◽

2019 ◽

Vol 42 ◽

Author(s):

Daniel J. Povinelli ◽

Gabrielle C. Glorioso ◽

Shannon L. Kuznar ◽

Mateja Pavlic

Keyword(s):

Temporal Reasoning ◽

Higher Order ◽

Important Case ◽

Human Cognition ◽

Relational Reasoning ◽

Dual Systems ◽

First Order ◽

Reasoning System ◽

Role Based

Abstract Hoerl and McCormack demonstrate that although animals possess a sophisticated temporal updating system, there is no evidence that they also possess a temporal reasoning system. This important case study is directly related to the broader claim that although animals are manifestly capable of first-order (perceptually-based) relational reasoning, they lack the capacity for higher-order, role-based relational reasoning. We argue this distinction applies to all domains of cognition.

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Quantitative EPMA of nitrogen : A tricky element in the electron-probe microanalyzer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132741 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1622-1623

Author(s):

G.F. Bastin ◽

H.J.M. Heijligers

Keyword(s):

Background Subtraction ◽

Electron Probe ◽

Detection System ◽

Higher Order ◽

Light Elements ◽

Strong Suppression ◽

Electron Probe Microanalyzer ◽

Quantitative Epma ◽

Peak Count ◽

Lead Stearate

Among the ultra-light elements B, C, N, and O nitrogen is the most difficult element to deal with in the electron probe microanalyzer. This is mainly caused by the severe absorption that N-Kα radiation suffers in carbon which is abundantly present in the detection system (lead-stearate crystal, carbonaceous counter window). As a result the peak-to-background ratios for N-Kα measured with a conventional lead-stearate crystal can attain values well below unity in many binary nitrides . An additional complication can be caused by the presence of interfering higher-order reflections from the metal partner in the nitride specimen; notorious examples are elements such as Zr and Nb. In nitrides containing these elements is is virtually impossible to carry out an accurate background subtraction which becomes increasingly important with lower and lower peak-to-background ratios. The use of a synthetic multilayer crystal such as W/Si (2d-spacing 59.8 Å) can bring significant improvements in terms of both higher peak count rates as well as a strong suppression of higher-order reflections.

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Texture measurements in Al2O3 using BEKP

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170773 ◽

1994 ◽

Vol 52 ◽

pp. 608-609

Author(s):

M. D. Vaudin ◽

J. P. Cline

Keyword(s):

Neutron Diffraction ◽

Rapid Method ◽

Crystallographic Orientation ◽

Specimen Surface ◽

X Ray Diffraction ◽

Anisotropic Crystal ◽

X Ray ◽

Verification Method ◽

Crystal Properties ◽

Backscattered Electron

The study of preferred crystallographic orientation (texture) in ceramics is assuming greater importance as their anisotropic crystal properties are being used to advantage in an increasing number of applications. The quantification of texture by a reliable and rapid method is required. Analysis of backscattered electron Kikuchi patterns (BEKPs) can be used to provide the crystallographic orientation of as many grains as time and resources allow. The technique is relatively slow, particularly for noncubic materials, but the data are more accurate than any comparable technique when a sufficient number of grains are analyzed. Thus, BEKP is well-suited as a verification method for data obtained in faster ways, such as x-ray or neutron diffraction. We have compared texture data obtained using BEKP, x-ray diffraction and neutron diffraction. Alumina specimens displaying differing levels of axisymmetric (0001) texture normal to the specimen surface were investigated.BEKP patterns were obtained from about a hundred grains selected at random in each specimen.

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Effects of Higher-Order Laue Zone reflections on structure images

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148083 ◽

1993 ◽

Vol 51 ◽

pp. 450-451

Author(s):

H. S. Kim ◽

S. S. Sheinin

Keyword(s):

Wave Vector ◽

Theoretical Calculations ◽

Reciprocal Lattice ◽

Image Plane ◽

Bloch Wave ◽

Dynamical Theory ◽

Higher Order ◽

Lattice Image ◽

Lattice Vector ◽

Image Position

The importance of image simulation in interpreting experimental lattice images is well established. Normally, in carrying out the required theoretical calculations, only zero order Laue zone reflections are taken into account. In this paper we assess the conditions for which this procedure is valid and indicate circumstances in which higher order Laue zone reflections may be important. Our work is based on an analysis of the requirements for obtaining structure images i.e. images directly related to the projected potential. In the considerations to follow, the Bloch wave formulation of the dynamical theory has been used.The intensity in a lattice image can be obtained from the total wave function at the image plane is given by: where ϕg(z) is the diffracted beam amplitide given by In these equations,the z direction is perpendicular to the entrance surface, g is a reciprocal lattice vector, the Cg(i) are Fourier coefficients in the expression for a Bloch wave, b(i), X(i) is the Bloch wave excitation coefficient, ϒ(i)=k(i)-K, k(i) is a Bloch wave vector, K is the electron wave vector after correction for the mean inner potential of the crystal, T(q) and D(q) are the transfer function and damping function respectively, q is a scattering vector and the summation is over i=l,N where N is the number of beams taken into account.

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Template mediated crystal engineering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017013x ◽

1994 ◽

Vol 52 ◽

pp. 480-481

Author(s):

Brigid R. Heywood ◽

S. Champ

Keyword(s):

Crystal Engineering ◽

Electrostatic Interactions ◽

Alkyl Chain ◽

Crystallographic Axis ◽

Two Dimensional ◽

Engineering Process ◽

Solution Interface ◽

Extensive Program ◽

Geometric Homology ◽

Long Alkyl Chain

Recent work on the crystallisation of inorganic crystals under compressed monomolecular surfactant films has shown that two dimensional templates can be used to promote the oriented nucleation of solids. When a suitable long alkyl chain surfactant is cast on the crystallisation media a monodispersied population of crystals forms exclusively at the monolayer/solution interface. Each crystal is aligned with a specific crystallographic axis perpendicular to the plane of the monolayer suggesting that nucleation is facilitated by recognition events between the nascent inorganic solid and the organic template.For example, monolayers of the long alkyl chain surfactant, stearic acid will promote the oriented nucleation of the calcium carbonate polymorph, calcite, on the (100) face, whereas compressed monolayers of n-eicosyl sulphate will induce calcite nucleation on the (001) face, (Figure 1 & 2). An extensive program of research has confirmed the general principle that molecular recognition events at the interface (including electrostatic interactions, geometric homology, stereochemical complementarity) can be used to promote the crystal engineering process.

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