A supramolecular zigzag chain of organometallic dipoles mediated by PF6 2- anions

Complex {Fe( 5-cyclopentadienyl)(PMe3)[P(OPh)3](4–NCC6H4NO2)} [PF6] has been characterized by spectroscopic and X-ray diffraction in order to evaluate the tuning of the electron density at the metal center and the extension ofthe delocalization on the molecule due to the presence of phosphite and phosphine co-ligands. The compound crystallizes in the centrosymmetric space group P21/c which destroys the possibility of exhibiting any quadratic NLO properties. The packing shows a supramolecular zigzag chain of antiparalell dimmers connected via the PF6 anions with C—H—F −distances ranging from 2.389 (7) to 2.667 (6)°A . Each zigzag chain is composed by isomeric organometallic fragments containing either R or S molecules. These chains are connected through weak intermolecular interactions (C—H· · ·C) forming a two dimensional plane along [101]

A supramolecular zigzag chain of organometallic dipoles mediated by PF6 2- anions

Complex {Fe( 5-cyclopentadienyl)(PMe3)[P(OPh)3](4–NCC6H4NO2)} [PF6] has been characterized by spectroscopic and X-ray diffraction in order to evaluate the tuning of the electron density at the metal center and the extension ofthe delocalization on the molecule due to the presence of phosphite and phosphine co-ligands. The compound crystallizes in the centrosymmetric space group P21/c which destroys the possibility of exhibiting any quadratic NLO properties. The packing shows a supramolecular zigzag chain of antiparalell dimmers connected via the PF6 anions with C—H—F −distances ranging from 2.389 (7) to 2.667 (6)°A . Each zigzag chain is composed by isomeric organometallic fragments containing either R or S molecules. These chains are connected through weak intermolecular interactions (C—H· · ·C) forming a two dimensional plane along [101]

A methodology to introduce sustainability into the Final Year Project to foster sustainable engineering projects

The introduction of sustainability skills into higher education curricula is a natural effect of the increasing importance of sustainability in our daily lives. Topics like green computing, sustainable design or environmental engineering have become part of the knowledge required by today’s engineers. Furthermore, we strongly believe that the introduction of this skill will eventually enable future engineers to develop sustainable products, services and projects. The Final Year Project is the last academic stage facing students and a step towards their future professional engineering projects. As such, it constitutes a rehearsal for their professional future and an ideal opportunity for reflecting on whether their Final Year Project is sustainable or not, and to what extent. It also provides a good tool for reviewing the lessons learned about sustainability during the degree course and for applying them in a holistic and integrated way. In this paper, we present a guide that allows both students and advisors to think carefully about the sustainability of engineering projects, in particular the Final Year Project.Postprint (author’s final draft

Synthesis of new donor/acceptor 5-cyclopentadienyl and 5-indenyliron(II) complexes with p-benzonitrile derivatives. Crystal structures of [Fe( 5-C5H5)(CO)(P(OC6H5)3)(p-NCC6H4NO2)][BF4]·CH2Cl2 and [Fe( 5-C9H7)(CO)(P(OC6H5)3)(p-NCC6H4NO2)][BF4]

New complexes of the type [Fe( 5-Cp or Ind)(L)(L )(p-NCR)][BF4] (L, L =CO, P(OC6H5)3, P(C6H5)3; R=C6H4N(CH3)2, C6H4NO2, (E)-C(H) C(H)C6H4NO2, (E)-C(H) C(H)C6H4N(CH3)2) have been synthesised and characterised. Spectroscopic data were analysed in order to evaluate the tuning of the electronic density at the metal centre and the extension of the -delocalisation on the molecule, due to the presence of coligands with different acceptor/donor abilities. The structures of two complexes [Fe( 5-C5H5)(CO)(P(OC6H5)3)(p-NCC6H4NO2)][BF4] and [Fe( 5-C9H7)(CO)(P(OC6H5)3)(p-NCC6H4NO2)][BF4] were determined by X-ray crystallographic analysis. The compounds crystallised in the centrosymmetric space groups P1 and P21/n, respectively. Bond distances within the nitrile ligand are discussed in order to evaluate the nature of iron–nitrile bonding in these complexes

Estimation of Hyperpolarizabilities of Organometallic Complexes by DFT

The research of nonlinear optical (NLO) materials has grown in the past decades due to the potential application in optical device technology, like data storage, communication and bio-sensing. For obtaining large molecular second-order nonlinear optical (SONLO) responses, i.e. large hyperpolarizabilities (β), molecules have to possess typical “push-pull” asymmetric structures. η5- Monocyclopentadienylruthenium(II) and iron(II) complexes presenting heterocyclic organic chromophores have proven to be promising systems in this field. Also the presence of a transition metal suggests that it is possible to switch the SONLO response of the material by changing its oxidation state, by electrochemical means for example. In this case, two distinct forms would be expected: the “switched on” form, with high β value; and the “switched-off” form, with negligible or substantially lower β. Herein, we show the application of Density Functional Theory (DFT) to the studies of SONLO properties of several organometallic complexes bearing thiophene based organic ligands as active NLO chromophores

Lesiones faciales en niños y adolescentes víctimas de agresiones

Child maltreatment may occur as the intentional use of power, effective or attempted, against children under 18 years old, that results or may result in actual or potential harm. It affects a vulnerable population, causing physical and/or emotional consequences persisting throughout their lives. This study aimed to characterize episodes of child maltreatment, with focus on facial injuries, in a Brazilian city (Teresina, PI). This is a retrospective study with a quantitative approach, carried out in the database at the Institute of Forensic MedicineinTeresina, between the years 2017 and 2019. All reports of bodily injury of children from 0 to 18 years were collected and statistically analyzed (SPSS 22.0). During the period analysis, 811 reports of bodily injury were identified. There was a predominance of female victims aged between 12 and 18 years old, the involvement of men with some family relationship with the victim was highly associated. Facial injuries represented 35.8% of the whole sample and 98.6% of those found in the head and neck region (41,6% of the total). The orbital (29.0%) was the most affected site, followed by the frontal (25.9%), malar (23.4%), labial (17.6%) and cheek area (11.4%). There is a high prevalence of injuries to the head and neck region, this factemphasizes the importance of a trained professional, especially a dental surgeon, in the analysis and interpretation of these injuries during forensic examination.info:eu-repo/semantics/publishedVersio

Studies of the Antiproliferative Activity of Ruthenium (II) Cyclopentadienyl-Derived Complexes with Nitrogen Coordinated Ligands

Four cationic ruthenium(II) complexes with the formula [Ru(η5-C5H5)(PPh3)2]+, with L = 5-phenyl-1H-tetrazole (TzH) 1, imidazole (ImH) 2, benzo[1,2-b;4,3-b′] dithio-phen-2-carbonitrile (Bzt) 3, and [5-(2-thiophen-2-yl)-vinyl]-thiophene-2-carbonitrile] (Tvt) 4 were prepared and characterized in view to evaluate their potentialities as antitumor agents. Studies by Circular Dichroism indicated changes in the secondary structure of ct-DNA. Changes in the tertiary structure of pBR322 plasmid DNA were also observed in gel electrophoresis experiment and the images obtained by atomic force microscopy (AFM) suggest strong interaction with pBR322 plasmid DNA; the observed decreasing of the viscosity with time indicates that the complexes do not intercalate between DNA base pairs. Compounds 1, 2, and 3 showed much higher cytotoxicity than the cisplatin against human leukaemia cancer cells (HL-60 cells)

Simulation of high brightness tapered lasers

Tapered semiconductor lasers have demonstrated both high power and good beam quality, and are of primary interest for those applications demanding high brightness optical sources. The complex non-linear interaction between the optical field and the active material requires accurate numerical simulations to improve the device design and to understand the underlying physics. In this work we present results on the design and simulation of tapered lasers by means of a Quasi- 3D steady-state single-frequency model. The results are compared with experiments on Al-free active region devices emitting at 1060 nm. The performance of devices based on symmetric and asymmetric epitaxial designs is compared and the influence of the design on the beam properties is analyzed. The role of thermal effects on the beam properties is experimentally characterized and analyzed by means of the numerical simulations. Tapered lasers with separate electrical contacts in the straight and tapered sections, based on symmetrical and asymmetrical epitaxial designs are also presented and analyze