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The interaction of small gas molecules as H2, N2, CO, H2S, NH3, SO2 and CH4 on Li-functionalized graphitic carbon nitride was investigated by using the density functional theory, to explore their gas adsorption properties. The calculated Eads values of all gas molecules on [Li g-C3N4]+ show that these gas molecules present favourable interaction with the lithium atom coordinated on the sheet. NH3 and SO2 molecules present strong interactions, with Eads values of −18.60 and −9.50 kcal mol−1. The natural bond orbital analysis indicates that donor orbitals belong to the lone pairs of oxygen, nitrogen, sulphur and carbon atoms from SO2, N2, NH3, H2S, CO molecules, and acceptor orbitals (LP*) from the lithium atom. Computational studies suggest that H2, N2, CO, H2S, NH3, SO2 and CH4 molecules on [Li g-C3N4]+ present physisorption. [ABSTRACT FROM AUTHOR]

The reaction of the tetramethylethylendiamine [(CH 3) 2 NCH 2 CH 2 N(CH 3) 2 ] with SnCl 2 in toluene provided the adduct dichloro-(1,2-bis(dimethylamino)ethane- N , N ′)-tin(II) with a tetracoordinate metal center and pseudo -trigonal bipyramidal geometry with a stereochemically active unshared electron pair in its vertex. This compound was characterized by IR, NMR (1H, 13C, and 119Sn) and X-ray studies. The X-ray crystal structure of tin(II) complex shows just one of these three possible isomers. The relative energies of the three different isomers, HOMO and LUMO orbitals, and NMR chemical shifts were calculated, using the density functional theory in order to determine the coordination number. [ABSTRACT FROM AUTHOR]

Reaction of the [HC(CMeNAr) 2 ]SnCl (Ar = 2,4,6-Me 3 C 6 H 2) with "GaI" in THF provided an unexpected transhalogenation reaction product [HC(CMeNAr) 2 ]SnI. The crystal structure shows a tin(II) ion with a distorted tetrahedral pyramidal geometry. Theoretical calculations, using density functional theory (B3LYP), suggest the probable reaction mechanism for transhalogenation. The activation energy for moving from reactant ([HC(CMeNAr) 2 ]SnCl to product [HC(CMeNAr) 2 ]SnI) is only 10.2 kcal/mol. The chloride ion is displaced by the iodine ion, probably by the help of the gallium atom when it is coordinated to the chlorine atom. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal-adorned borophene has a remarkable capacity for coordinating glucose. • The values of E ads (−34.22 to −43.69 kcal/mol) suggest glucose physisorption to [MB 36 ]+ (M = Li, Na, K). • Systems with 1+ oxidation state are more promising to be applied as adsorbents of this drug. In view of the urgent need for developing new materials for biomedical applications, we report on multi-facet study of functionalized borophene as a possible sensor or transporter of glucose. The adsorption of a glucose molecule on [MB 36 ]+ (M = Li, Na, K), [MB 36 ]2+ (M = Be, Mg, Ca), and [MB 36 ]3+ (M = B, Al, Ga) complexes were studied both in gas and in water phase, conforming that [MB 36 ]+, [MB 36 ]2+, [MB 36 ]3+ are highly efficient as glucose adsorbers with the binding energies of −34 to −135 kcal/mol in the gas phase, and −12 to −111 kcal/mol in water as calculated with the PBE0-D3/def2-TZVP. Borophene adorned with beryllium have the highest adsorption energies, while the complexes with Li, Na and K are characterized with lower binding energy values. Thus, the systems with 1+ oxidation state are more promising for intelligent drug delivery, while [MB 36 ]+, [MB 36 ]2+, [MB 36 ]3+ are more suitable for designing biosensors of glucose. [ABSTRACT FROM AUTHOR]

Multi-stimuli responsive fluorescent (MSRF) materials can change their photophysical properties upon application of two or more external stimulus such as temperature, mechanical stress, and acid-base vapors. These smart materials have received great attention due to their evident advantages in sensors, probes, displays, data recording, and bioimaging. The synthesis and characterization of (E)-4-hydroxy-N′-(2-hydroxy-4-methoxybenzylidene) benzohydrazide ( 1 ) and their two new organoboron compounds are described [4-(10-methoxy-2-phenylbenzo[ h ] [1,3,5,6,2]dioxadiazaboronin-4-yl)phenol ( 2 ) and 4,4′-(2,2′-(1,4-phenylene)bis(10-methoxybenzo[ h ] [1,3,5,6,2]dioxadiazaboronine-4,2-diyl))diphenol ( 3 )]. The compounds were characterized by NMR ( 1 H, 13 C), UV/vis, fluorescence spectroscopy and high-resolution mass spectrometry (HRMS). The photophysical properties of organoboron were investigated; we found low fluorescence emission (Compound 2 Φ F : 0.89%, compound 3 Φ F : 0.93%) but in solid state showed interesting luminescent properties such as reversible thermochromism, piezochromism, vapochromism, and mechanochromism are reported. [ABSTRACT FROM AUTHOR]

[Display omitted] • The [M/g-C 3 N 4 ]+ complexes have been seen as interesting adsorbents of metformin. • M/g-C 3 N 4 , M: Li, Na, K have values of 39.29–19.13 kcal/mol favorable for drug delivery. • NBO shows donor orbitals belong to the nitrogen atoms of metformin. Metformin is one of the important anti-diabetic drugs. DFT calculations have been performed to study properties of adsorption of metformin onto [M/g-C 3 N 4 ]+,+2,+3 , where M: Li, Na, K, Be, Mg, Ca, B, Al, and Ga. Optimized structures of all systems were calculated using the ONIOM computational method. The results were used to calculate the absorption energy (E ads) with the PBE0-D3(BJ)/def2-TZVP method. The adsorption energy values for the most stable configurations are 19.1–131.6 kcal/mol. By adsorption of metformin on [M/g-C 3 N 4 ]+,+2,+3 surfaces, the ionization potential values of [M/g-C 3 N 4 ]+ , M: Li, Na and K are low, which means that the stability of M: Li, Na and K systems are higher than the other systems (groups 2 and 3). The [M/g-C 3 N 4 ]+ complexes have been seen as interesting adsorbents of metformin molecule. [ABSTRACT FROM AUTHOR]

[Display omitted] • The computational studies reveal physisorption of adrucil on [La-CTF-0]3+ system. • The lanthanum atom on CTF-0 facilitates the adsorption of adrucil molecule. • The NBO analysis shows the adrucil acts as a strong donor towards the CTF-0. Fluorouracil is a chemotherapy medication used in the treatment of many cancers. Motivated in the development of new drug delivery, in the present work, the adsorption of adrucil drug on [La-CTF-0]+3 was studied. Electron and interaction properties of [La-CTF-0]+3 with the adrucil molecule have been explored by DFT. The optimized structure and energy were investigated usin the PBE0/def2-TZVP method. Results suggest that adrucil molecule can be adsorbed physically on the [La-CTF-0]+3, with adsorption energy of 69.82 kcal/mol. The HOMO-LUMO orbitals of the system indicate that the electron properties of the [La-CTF-0]3+ are slightly altered after the adsorption of the drug on [La-CTF-0]+3. The natural bond orbital calculation shows charge transfer between the electron donor oxygen on adrucil and the lanthanum atom, acceptor. This research provides new insights into the development of drug delivery systems. [ABSTRACT FROM AUTHOR]