scholarly journals Symmetric Fluoroborate and its Boron Modification: Crystal and Electronic Structures

Crystals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 662
Author(s):  
Błażej Dziuk ◽  
Borys Ośmiałowski ◽  
Bartosz Zarychta ◽  
Krzysztof Ejsmont ◽  
Lilianna Chęcińska
Keyword(s):  
Charge Transfer ◽  
Boron Atom ◽  
Electronic Structures ◽  
Steric Effect ◽  
Crystal Packing ◽  
Real Space ◽  
Hirshfeld Surface ◽  
Boron Modification ◽  
Donor Acceptor ◽  
A Charge

Four boron-carrying molecules were synthesized and purified. These were found to be (a) relatively neutral with respect to the parent BF derivative and (b) functionalized by donor–acceptor groups resulting in a charge transfer within the molecule. The study discusses the steric effect and the influence of the substitution of the side rings on the surroundings of the boron atom. Electronic structures were characterized by real-space bonding indicators. Hirshfeld surface and energy frameworks tools were applied to examine the crystal packing features.

scholarly journals Nanopore-induced host–guest charge transfer phenomena in a metal–organic framework

2018 ◽  
Vol 9 (13) ◽  
pp. 3282-3289 ◽  
Author(s):  
S. Yamamoto ◽  
J. Pirillo ◽  
Y. Hijikata ◽  
Z. Zhang ◽  
K. Awaga
Keyword(s):  
Charge Transfer ◽  
Self Assembly ◽  
Metal Organic Framework ◽  
Donor And Acceptor ◽  
Organic Electron ◽  
Donor Acceptor ◽  
Metal Organic ◽  
Bulk Scale ◽  
A Charge ◽  
Organic Framework

Using the “crystal sponge” approach, weak organic electron donor molecules were impregnated and evenly distributed in a crystal of a metal–organic framework (MOF), with the self-assembly of the donor–acceptor pairs with electron acceptor ligands. The nanopores of the MOF confined them and induced a charge transfer phenomenon, which would not occur between donor and acceptor molecules in a bulk scale.

scholarly journals N-Substitution of acridone with electron-donating groups: crystal packing, intramolecular charge transfer and tuneable aggregation induced emission

RSC Advances ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 7092-7098 ◽  
Author(s):  
Renfei Liu ◽  
Guanxing Zhu ◽  
Gang Zhang
Keyword(s):  
Charge Transfer ◽  
Transfer Process ◽  
Intramolecular Charge Transfer ◽  
Crystal Packing ◽  
Charge Transfer Process ◽  
Aggregation Induced Emission ◽  
Donor Acceptor ◽  
Electron Donating Groups

Triphenylamine functionalized acridone leads to a donor–acceptor system with intramolecular charge transfer process and tuneable aggregation induced enhanced emission.

scholarly journals The charge percolation mechanism and simulation of Ziegler-Natta polymerizations. Part III. Oxidation states of transition metals

2006 ◽  
Vol 71 (4) ◽  
pp. 357-372 ◽  
Author(s):  
Branka Pilic ◽  
Dragoslav Stoiljkovic ◽  
Ivana Bakocevic ◽  
Slobodan Jovanovic ◽  
Davor Panic ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Oxidation States ◽  
Support Surface ◽  
Active Centers ◽  
Active Centre ◽  
Whole Process ◽  
Oxidation Reduction ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
A Charge

The oxidation state of the transition metal (Mt) active centre is the most disputable question in the polymerization of olefins by Ziegler-Natta (ZN) and metallocene complexes. In this paper the importance and the changes of the Mt active centers are presented and discussed on the basis of a charge percolation mechanism (CPM) of olefin polymerization. Mt atoms can exist in different oxidation states and can be easily transformed from one to another state during activation. In all cases, the Mt atoms are present in several oxidation states, i.e., Mt+(n-1), Mt+(n) to Mt+(n+1), producing an irregular charge distribution over the support surface. There is a tendency to equalize the oxidation states by a charge transfer from Mt+(n-1) (donor) to Mt+(n+1) (acceptor). This cannot occur since the different oxidation states are highly separated on the support. However, monomer molecules are adsorbed on the support producing clusters with stacked ?-bonds, making a ?-bond bridge between a donor and an acceptor. Once a bridge is formed (percolation moment), charge transfer occurs. The donor and acceptor equalize their oxidation states simultaneously with the polymerization of the monomer. The polymer chain is desorbed from the support, freeing the surface for subsequent monomer adsorption. The whole process is repeated with the oxidation-reduction of other donor-acceptor ensembles.

scholarly journals Ultra-Weak Cell Radiation as an Impulse to Activate Biological Signal Transmission Paths

2021 ◽  
Vol 4 (3) ◽  
Keyword(s):  
Quantum Mechanics ◽  
Charge Transfer ◽  
20Th Century ◽  
Signal Transmission ◽  
Molecular Structures ◽  
Atoms And Molecules ◽  
Biological Signal ◽  
Donor Acceptor ◽  
Molecular Signal ◽  
A Charge

Basic physical research at the beginning of the 20th century developed concepts of the energetic properties of atoms and molecules with quantum mechanics, which increasingly also included biological structures. Considerations of a “charge transfer” or also known as “donor-acceptor interactions” of the movement of electrons between molecular structures developed. This energetic process is the basis of the ultra-weak cell radiation, which is to be discussed as the basis for the activation of the molecular signal transmission.

scholarly journals Crystal structure and Hirshfeld surfaces analysis of Heterocyclic-and circulenes

2022 ◽  
Vol 355 ◽  
pp. 01020
Author(s):  
Nataliya Karaush-Karmazin ◽  
Glib Baryshnikov ◽  
Boris Minaev
Keyword(s):  
Crystal Structure ◽  
Charge Transfer ◽  
Intermolecular Interactions ◽  
Flat Surface ◽  
Crystal Packing ◽  
Shape Index ◽  
Hirshfeld Surface ◽  
Surface Patches ◽  
Main Charge ◽  
Efficient Charge

The crystal structure of the new diazatrioxa[9]circulene and tetrahydro-diazatetraoxa[10]circulene which represent the first synthesized representatives of “higher” hetero[n]circulenes with n>8, was analyzed in details. Hirshfeld surface analyses, the dnorm surfaces and two-dimensional fingerprint plots were used to verify the contributions of the different intermolecular interactions within the crystal structure of diazatrioxa[9]circulene and tetrahydro-diazatetraoxa[10]circulene. The Hirshfeld surface analysis of the crystal structure clarifies that the most important contribution for crystal packing is from H∙∙∙H and C∙∙∙H intermolecular interactions for both circulenes. The shape-index surface shows that in the case of diazatrioxa[9]circulene two sides of the molecules are involved with the same contacts in neighbouring molecules and curvedness plots show flat surface patches that are characteristic of planar stacking. Such face-to-face structural organization provides the main charge transfer pathway in [9]circulene. In the case of [10]circulene, the area involved in the same contacts is much less, however, two types of intermolecular packing modes can form such flat surface patches at curvedness plots which is useful for more efficient charge transfer.

scholarly journals A Charge-Transfer Salt Based on Ferrocene/Ferrocenium Pairs and Keggin-Type Polyoxometalates

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3150 ◽  
Author(s):  
Beñat Artetxe ◽  
Amaia Iturrospe ◽  
Pablo Vitoria ◽  
Estibaliz Ruiz-Bilbao ◽  
José S. Garitaonandia ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Diffuse Reflectance ◽  
Crystal Packing ◽  
X Ray Diffraction ◽  
X Ray ◽  
Keggin Type ◽  
Vis Spectroscopy ◽  
Keggin Anions ◽  
Structural Database ◽  
A Charge

A new hybrid inorganic-organometallic salt has been obtained from the reaction of the Keggin-type silicotungstate anion with ferrocene in a water/methanol mixture as a result of the partial oxidation of ferrocene molecules to ferrocenium cations. Single-crystal X-ray diffraction analysis reveals the presence of four ferrocenium (FeIII) cations and one ferrocene (FeII) molecule per plenary Keggin anion in the crystal structure of [FeIII (Cp)2]4[SiW12O40]·[FeII(Cp)2]·2CH3OH (1). Compound 1 thus constitutes the first example in the literature in which ferrocenium and ferrocene species coexist in the structure of a polyoxometalate-based salt. The two crystallographically independent ferrocenium species in the asymmetric unit of 1 exhibit different configurations: One displays an eclipsed conformation with ideal D5h symmetry, whereas the conformation in the other one is staggered D5d. The crystal packing of 1 can be best described as an organometallic sub-lattice of ferrocenium and ferrocene species linked by a network of π-π interactions that generates rectangular cavities of about 14 × 10 Å in which strings of Keggin anions and methanol molecules are hosted, further connected to each other via weak OPOM···CMeOH-OMeOH···OPOM type hydrogen bonds. The charge-transfer nature of the salt has been studied by solid-state diffuse reflectance UV-Vis spectroscopy and the presence of magnetically isolated FeIII/FeII centres has been confirmed by Mössbauer spectroscopy. A topological study carried out on all of the pristine ferrocenyl species deposited in the Cambridge Structural Database (CSD) has allowed two main conclusions to be drawn: (1) these species tend to adopt extreme conformations (either eclipsed or staggered) with less than a 15% of examples showing intermediate states and (2) the oxidation state of the iron centres can be unequivocally assigned on the basis of a close inspection of the Fe···Cp distances, which allows ferrocene neutral molecules and ferrocenium cations to be easily distinguished.

Stepwise fabrication of donor/acceptor thin films with a charge-transfer molecular wire motif

2016 ◽  
Vol 52 (97) ◽  
pp. 13983-13986 ◽  
Author(s):  
Yoshihiro Sekine ◽  
Taiga Yokoyama ◽  
Norihisa Hoshino ◽  
Manabu Ishizaki ◽  
Katsuhiko Kanaizuka ◽  
...  
Keyword(s):  
Thin Films ◽  
Charge Transfer ◽  
Layer By Layer ◽  
Molecular Wire ◽  
Layer Technique ◽  
Donor Acceptor ◽  
A Charge ◽  
Transfer Chain ◽  
Layer By Layer Technique ◽  
Chain Compound

Novel thin films composed of a donor/acceptor charge-transfer chain compound were fabricated by a layer-by-layer technique using complexation of a paddlewheel-type [Ru2II,II] complex with a DCNQI derivative on an ITO substrate with a pyridine-substituted phosphonate anchor.

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