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This study aimed to investigate the impact of insoluble glucan on the self-assembly kinetics and physicochemical attributes of starch microparticles (SMPs). It was found that the inclusion of insoluble glucans (SMP-ISG) significantly accelerated both the formation and crystallization processes, demonstrating a rate approximately 1.5 times faster compared to SMPs without insoluble glucans (SMP-SG). This acceleration in kinetics was attributed to the presence of insoluble long chains, which facilitated molecular aggregation and crystal growth. Additionally, SMP-ISG displayed changes in particle size (0.74 μm) and relative crystallinity (19.9%) when compared to SMP-SG (0.62 μm and 17.7%, respectively) suggesting that insoluble glucans contribute to the enhancement of both size and crystallinity, which support the hypothesis of their role in molecular aggregation and crystal nucleation. However, despite these beneficial effects, SMP-ISG showed increased susceptibility to agglomeration, which compromised the stability of the colloidal system. During the formation of SMP-ISG, alignment with insoluble glucans facilitated the creation of more stable double-helix structures, leading to elevated enthalpy and transition temperatures. In SMP-ISG, the digestion rate was reduced due to a higher content of resistant starch, whereas SMP-SG exhibited a higher content of slowly digestible starch. Consequently, it is possible to customize the properties of SMPs by precisely controlling the amount of insoluble glucans during SMP formation, thereby broadening their utility in various food and industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • H 2 O molecules were identified as CAS of Co2+ doped SnO 2 (2 2 1) crystal plane. • Co2+ doping leads to the formation of oxygen defects on the crystal plane. • The adsorption of O 2 and N 2 molecules reduces the crystal surface conductivity. • The remodeling of H 2 O molecules on the crystal surface affects the electrical conductivity. In this paper, Co2+-doped SnO 2 (2 2 1) crystal plane materials were synthesized, and the remodeling effect of the H 2 O molecular crystal plane and molecular adsorption behavior was studied by Density Functional Theory (DFT) simulation. The DFT simulation results show that the remodeling mechanism of H 2 O molecules on the crystal plane is as follows: the doping of Co2+ makes the crystal planes form oxygen defects on the crystal planes, which are further remodeled by H 2 O molecules during the synthesis process to be hydroxylated. The hydroxylated crystal surface adsorbs the O 2 molecule (hydrogen bond), and then adsorbs the H 2 O molecule on the adsorbed O 2 molecule (hydrogen bond). The theoretical simulation results show that the remodeling of the H 2 O molecule affects the electrical conductivity of the crystal plane. After the hydroxylated crystal plane further adsorbs O 2 , N 2 and H 2 O molecules, the electrical conductivity of the crystal plane increases, weakly increases and decreases, respectively. [ABSTRACT FROM AUTHOR]

Recently invented AlteQ method for estimation of electron density of compounds was developed in the current work. AlteQ Slater-type electron density functions were approximated by Gaussians for fast estimation of electron overlaps. The obtained approach was named AlteQ-G. AlteQ-G 3D maps of electron density computed for organic and inorganic molecules were compared to the experimentally obtained high-resolution X-ray diffraction (HRXRD) data. Different electron-based characteristics derived from AlteQ-G molecular description were suggested and applied for quantitative “structure-property” relationships (QSPR) study. Furthermore, obtained relationships showed that different physicochemical properties of compounds such as enthalpy, entropy, Gibbs free energy, pKa values, liquid densities can be estimated using AlteQ-G molecular description. The physicochemical properties of compounds as well as molecular and atomic electron-based descriptors can be computed on-line using AlteQ-G method at www.chemosophia.com web page. [ABSTRACT FROM AUTHOR]

Copyright of Kobunshi Ronbunshu is the property of Society of Polymer Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • Fabrication strategy based on shrinking a laser-patterned hydrogel template enables construction of nanodevices. • Polyacrylate-polyacrylamide hydrogel is exposed to a femtosecond laser pulse using a light sheet approach. • Patterned hydrogel acts as a template for assembly of metal, alloy, oxide, diamond, molecular crystal, and biomaterial particles. • Strategy offers fabrication route for nanodevices such as encrypted optical storage devices and microelectrodes. [ABSTRACT FROM AUTHOR]

Natural hydroxyapatite provides certain strength and stiffness to biological bones, and most of the studies on the strength of bone tissues have been carried out on hydroxyapatite (HAP). However, the Ca/P ratio of hydroxyapatite in bones is actually about 1.50, and the natural hydroxyapatite belongs to calcium-deficient hydroxyapatite (CDHA) with Ca vacancy defects. Therefore, this work focused on the effect of Ca vacancy defects on CDHA crystals through investigating the generation and expansion of microcracks under uniaxial tensile loading by combining molecular dynamics and first principles method. A series of crystal models with different Ca vacancy ratios are constructed and find that Ca vacancies degrade the mechanical properties of hydroxyapatite. Meanwhile the fracture behavior of crystals is detailed and find that the cracks arise at vacancies and extend along the direction of vacancies. Also, first-principles calculation is performed to reveal the mechanism of crack formation in MD simulations. It is found that the decrease of Ca–O bonding of CDHA causes the decrease of the stability of the crystal structure by analyzing the DOS of HAP and CDHA, and the cracks originate from Ca vacancies. This work performs more realistic simulations of CDHA with calcium vacancy defects in actual bone tissue and directly reveals the development and progression of bone fragility at the nanometer scale. [ABSTRACT FROM AUTHOR]

In this study, the crystal structures of the 2-amino-1-methyl-1H-benzimidazol-3-ium(O,O-di-isopropylphosphorodithioate) ionic liquid - [C 8 H 10 N 3 ]+ [C 6 H 14 O 2 P 1 S 2 ]– [(MAB+H)DIPDTP] and bis (1-methyl-1 H-benzimidazol-2-amine)- bis (O,O-di-isopropyl phosphorodithioato)-cadmium(II) - C 28 H 46 Cd 1 N 6 O 4 P 2 S 4 [Cd(MAB) 2 (DIPDTP) 2 ]) are characterized by X-ray diffraction analysis. Organic ligands – O,O-di-isopropylphosphorodithioate (DIPDTP), 1-methyl-1 H-benzimidazol-2-amine (MAB), and new acid-base bi-functional protonic ionic liquid ([(MAB+H)DIPDTP]) – are immobilized into commercial polymeric crosslinked polystyrene-divinylbenzene sorbent (PAD600) and their sorption capacity for Cd2+ from aqueous solution is evaluated. The successful immobilization of DIPDTP and MAB into macroporous polystyrene is confirmed by means of scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and N 2 -BET analysis. The Cd2+ sorption efficiency of PAD600-MAB-DIPDTP sorbent increases due to the combination of physical adsorption and extraction, surface complexation, and formation of metal complexes, chelates, and poorly soluble compounds. The adsorption equilibrium data are better fitted to the Freundlich isotherm models. The overall sorption is exothermic and spontaneous and follows a pseudo-second-order kinetic model. This indicates a complex sorption mechanism, including both physical adsorption and strong chemical interaction, dissociation constant, acid-base properties, and reaction condition (pH, temperature, concentration, etc.). The novel composite material can be a promising adsorbent for Cd2+ removal from contaminated water. [Display omitted] • Novel acid-base and bi-functional benzimidazolium ionic liquid (IL) is synthesized. • Crystal and molecular structures of IL are studied by X-ray diffraction analysis. • IL is immobilized into macroporous polystyrene to improve its Cd2+ sorption. • pH = 8–10 is found to be favorable for spontaneous Cd2+ sorption. • Cd2+ sorption mechanism includes extraction-sorption processes and physical adsorption. [ABSTRACT FROM AUTHOR]

Dispersion corrected density functional theory (DFT-D) calculation was performed to examine the structural response of 1,3-Diamino-2,4,6-trinitrobenzene (DATB) in the pressure range of 0–15 GPa. The calculated results of the crystal structure, molecular geometry and intermolecular close contacts were in good agreement with the experimental data at ambient pressure. To get further insight into the structural response to pressure of DATB, Hirshfeld surfaces analysis was carried out to elucidate the varied crystal environments. The considerable changes in the pressure dependence of the geometry and various intermolecular close contacts suggested a phase transition occurring around 6.5 GPa. Furthermore, the current study indicated that the Hirshfeld surfaces analysis provided a visual motif for understanding the pressure effect on the energetic molecular crystal DATB. [ABSTRACT FROM AUTHOR]

Topological evolution of ligand to its complex because of weak interactions. [Display omitted] • Ligand resulted in a 16-c uninodal net of unknown topological type with point symbol {345.467.58}. • Complex showed a 12,14-c net with 12,14T5 topological type. • Multilevel analysis of ligand and its complex leads to interesting structure-topology relation. • Hirshfeld and 2D finger plot analysis of the molecule help to understand the types and strength of non-covalent interactions. Properties of single crystal depend on molecular architecture in the lattice which is related to its topology. The topology of the molecule come into existence due to its different non-covalent interactions. For this reason, Hirshfeld and molecular electrostatic potential analysis of the molecule help to understand the types and strength of non-covalent interactions. The topological analysis of [Cu(qmbn)(q)(Cl)] complex was investigated with the help of density functional theory, Hirshfeld and MEP study. In molecular packing, it showed 12,14-c net with 12,14 T5 topological type. For the overall structure, the subnet of 12,14-c underlying net (UN) with 1 M2-1topological type was observed. The hydrogen bonding, Cl-π, weak π...π and van der Waals interactions play important role to maintain the molecular topology. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights: [•] Molecular crystalline NH4N3 and N2H5N3 have been studied. [•] NH4N3 and N2H5N3 are energetically stable. [•] Ionic bonds between in NH4N3 have been shown. [•] Ionic bonds between in N2H5N3 have been presented. [Copyright &y& Elsevier]

Abstract: The novel non-covalent interaction (NCI) descriptor proposed by Johnson et al. (J. Am. Chem. Soc. 2010, 132, 6498–6506) and based on the reduced density gradient (RDG), is applied to three molecular crystals, spanning a wide range of NCI classes. The key-aspect of this work is to contrast the NCI description obtained using the RDG of the electron density (ED) derived from single-crystal X-ray diffraction data with that calculated from the RDG of the corresponding Independent Atom Model (IAM) density. It is shown that the RDG isosurfaces obtained from the simpler, unperturbed model density are often able to highlight the same interactions revealed by the corresponding surfaces using the crystalline density, but differ systematically in size and are generally much less structured than these latter. A qualitative rationale for such differences is provided for the first time. Our results question the use of the simpler density model to study NCI in large biological systems. [Copyright &y& Elsevier]

Presents several studies about chemistry which received the Chemical Society of Japan Award for Creative Work for 2003. "Design of Functional Molecular Crystals by Controlling Intermolecular Interactions," by T. Inabe; "Molecule-Based Magnets in Heterospin Systems," by N. Koga and S. Karasawa; "Electronic Structure of Sulfimides: A Theoretical Study," by P. S. Kumar, P. Singh, P. Uppal and P. V. Bharatam.

A derivative of the metal dibenzoylmethanate (DBM) host type, accomplished through the chemical modification of the DBM ligand, is reported for the first time. The new ligand, (1-naphthoyl)benzoylmethanate (NBM) differs from the parent DBM by an additional phenylene ring. Three new complexes [NiA2(NBM)2], with pyridine (Py), 4-methylpyridine (4-MePy) and 4-phenylpyridine (4-PhPy) is A, were synthesized and studied for host properties. Complexes with Py and 4-MePy were isolated as solvent-free forms and did not show any ability to form inclusion compounds with ten solvents tested. Single-crystal XRD study revealed van der Waals type of crystal structure of the complexes. The nickel atom is octahedrally coordinated by two chelating NBMs in the equatorial plane and two terminal pyridines. Naphthyl ligands turn almost perpendicular to the equatorial plane of the complex filling the pocket space which usually accommodates guest species in metal DBM analogues. This ‘self-inclusion’ of its own fragment, that the molecule demonstrates, explains the inability of the complexes to entrap guest solvents. The complex with 4-PhPy forms inclusion compounds with chloroform, benzene, tetrahydrofuran and acetone, the compounds have 1:2 host to guest ratio and are isostructural. A possible explanation of such a difference is the larger size of the pocket which now cannot be completely filled with the naphthyl fragment. [Copyright &y& Elsevier]

• Optimized molecular structure was analyzed using DFT and the quantum chemical calculations were carried out. • Multipole analysis is done to analyse the aspherical distribution of charges. • Bonding between atoms were analyzed from (3, −1) critical points in charge density. • ELF and LOL maps were used to quantify the interaction. • The reactive locations of the molecule were identified using Molecular Electrostatic Potential. Extensive quantum chemical calculations were carried out for the molecule with B3LYP/6311G++(d,p) level of theory. The molecular packing of the crystal is stabilized by C H...N and C H...O interactions and those interactions were investigated through Hirshfeld surface analysis. Aspherical distribution of charges was estimated using Hansen-Coppens multipole formalism and the effect of temperature on charge density was analyzed. Bader's AIM theory was used to perform the topological analysis of electron density which disclose the strength and nature of atom-atom interaction. Stability of the molecule arising from hyper conjugative interactions and charge delocalization was examined using Natural Bond Orbital analysis and it also confirms the existence of C H...N and C H...O hydrogen bonds. Frontier Molecular Orbital analysis was carried out and the molecule is found to be a good electrophile with the electrophilicity index of 9.7349 eV. Molecular Electrostatic Potential was used to identify the possible reactive locations of the molecule. [ABSTRACT FROM AUTHOR]

• The crystal and molecular structure of DMNA were investigated using the dispersion corrected DFT. • The identification, quantitative measurement of intermolecular close contacts in DMNA were presented. • The high-pressure Raman spectroscopy of DMNA was calculated by the linear response method. The structural and vibrational properties of the typical energetic compound DMNA were studied up to 15 GPa by dispersion-corrected density functional theory (DFT-D) calculations. The calculated crystal structure and vibrational spectra at ambient conditions matched well with the previous experiment and quantum chemical calculations. Further, the lattice parameters, molecular geometry, intermolecular close contacts and Raman spectrum were also examined under high pressure. Although an anisotropic compressibility and subtle change in the bond angles was presented, no evidence of phase transition was observed in our pressure range. [ABSTRACT FROM AUTHOR]

Metathetical coupling of an η[sup5]-fullerene ruthenium complex Ru(η[sup5]-C[sub60]Me[sub5])Cl(CO)[sub2] and sodium cyclopentadienide gives a molecular hybrid of ruthenocene and fullerene, Ru(η[sup5]-C[sub60]Me[sub5]) (η[sup5]-C[sub5]H[sub5]) (bucky ruthenocene), the structure of which was determined by spectroscopic and crystallographic analyses. The molecule shows unique reactivity among known ferrocene and ruthenocene compounds. [ABSTRACT FROM AUTHOR]

We prepared a series of copper(I) polynuclear complexes bridged by three different alkyl substituted pyrazolate anions. From X-ray analysis, these differences reflected their molecular structures. These structural changes also reflected some properties in their IR, far-IR, UV-vis, and NMR spectra. [ABSTRACT FROM AUTHOR]

A [2]rotaxane was synthesized in a high yield from a dumbbell-shaped sec-ammonium salt having trityl thioether and 3,5-di-t-butylphenyl groups at the both ends and dibenzo-24-crown-8-ether, through the slipping, utilizing the reversible cleavage-rebondage of the trityl thioether linkage. [ABSTRACT FROM AUTHOR]

The dry bead milling of a mixture of anthracene crystals and a tiny amount tetracene in the presence of surface-modified silica nanoparticles led to the fluorescence quenching of anthracene due to the doping of tetracene, supporting the occurrence of crystal mixing under dry conditions. [ABSTRACT FROM AUTHOR]

A molecular crystal of 6-[2-propyl-4-(4-pyridylazo)phenoxy] hexanoic acid prepared by sublimation showed two thermally reversible transitions at 17 and 172 °C on heating. Temperature dependence of its X-ray diffraction profile analyzed on the basis of its crystal structure revealed that the reversible transitions were related to a thermally induced hierarchical structural transformation involving cleavage of a C-H···O hydrogen bond, followed by cleavage of a O-H···N hydrogen bond. [ABSTRACT FROM AUTHOR]

A molecular crystal of octamethylene (S,S)-bis(2-hydroxy-3,3,3-trifluoropropanoate) with an ultramicroporous tunnel (φ = 2.5-2.8 Å) starts to adsorb argon (φ = 3.6 Å) at 150-140 K with 7% increase of the one direction of the orthorhombic unit cell. The alteration of the unit cell size indicates the penetration of argon into the tunnel and the soft nature of the microporous molecular crystal. [ABSTRACT FROM AUTHOR]

An abstract of the article "The Importance of Cooperative Interactions and a Solid-State Paradigm to Proteins: What Peptide Chemists Can Learn From Molecular Crystals," by J. J. Dannenberg is presented.