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Complexos de ouro(I) derivados do adamantano: síntese, atividade citotóxica e potencial de inibição da tiorredoxina redutaseGarcia, Adriana 06 March 2015 (has links)
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Previous issue date: 2015-03-06 / PROQUALI / Este trabalho descreve a síntese, caracterização, atividade citotóxica e potencial de inibição da
enzima tiorredoxina redutase (TrxR) de quatro novos complexos de ouro(I) derivados do
adamantano com 1,3,4-oxadiazol ou 1,3-tiazolidina-2-tiona e alquil ou aril fosfinas. Os
compostos foram avaliados quanto à citotoxicidade em três linhagens de células tumorais e
uma linhagem normal, sendo determinada a concentração inibitória de cinquenta por cento da
viabilidade celular (CI50) e o índice de seletividade (IS). Uma das mais importantes aplicações
de complexos metálicos na clínica médica é no tratamento do câncer como é o caso da
Cisplatina [(cis-diamindicloroplatina(II)] e seus derivados. Entretanto, existem problemas
associados ao seu uso, especialmente a resistência celular desenvolvida por alguns tipos de
tumor e os graves efeitos colaterais, que geram uma demanda por compostos mais ativos
contra o câncer e menos tóxicos para o paciente. Dentro deste contexto, a busca por
complexos contendo diferentes metais que possibilitem novos alvos celulares surgiu como
forma de contornar tais problemas. A ação de complexos com platina ocorre
preferencialmente sobre o DNA enquanto a ação do ouro está relacionada à inibição da
enzima TrxR que participa do balanço redox intracelular. Com o intuito de potencializar a
ação dos complexos de ouro(I) selecionamos os ligantes derivados do adamantano com anel
heterocíclico oxadiazol ou tiazolidina e fosfinas (alifáticas ou aromáticas) que estão presentes
em substâncias bioativas. Os compostos sintetizados foram caracterizados por CHN, RMN 1H
e 13C, IV, Raman, TG além de difração de raios X por monocristal no caso dos ligantes e do
complexo 1 {trifenilfosfino[5-adamantil-1,3,4-oxadiazol-2-tiolato(κS)]ouro(I)}. Todos os
complexos foram mais ativos sobre as células tumorais que os ligantes livres e foram mais
eficientes e seletivos do que a Cisplatina para a linhagem de células de melanoma (B16-F10).
O complexo 4 {Cloreto de trietilfosfino[(metil-1-adamantano)1,3-tiazolidina-2-
tiona(κS)]ouro(I)} apresentou valores de CI50 próximos a Auranofina [2,3,4,6-tetra-o-acetil-1-
tio-β-D-glicopiranosato-trietilfosfinouro(I)] e maior seletividade. Quanto a capacidade de
inibição da enzima TrxR, os complexos com trietilfosfina foram mais eficientes, alcançando
porcentagem de inibição próxima a da Auranofina. Notamos uma relação entre a capacidade
de inibição da TrxR e a citotoxicidade, o que sugere o mecanismo de ação destes compostos
de ouro via inativação da enzima. Dessa forma, o presente trabalho apresenta uma importante
contribuição para a química de coordenação dos complexos de ouro(I). / This work describes the synthesis, characterization, cytotoxic activity and potential inhibition
of thioredoxin reductase (TrxR) of four new gold (I) complexes with novel ligands derived
from adamantine, 1,3,4-oxadiazole or 1,3-thiazolidine-2-thionering and alkyl or aryl
phosphines. The cytotoxicity of compounds was investigated in three tumor cell lines and one
normal cell to determine the inhibitory concentration of fifty percent of cell viability (IC50)
and selectivity index (SI). One of the most important applications for metal complexes such
as Cisplatin [cis-diamindichloroplatinum(II)] and derivatives is in cancer treatment. However,
there are several problems associated with their use, especially cellular resistance, developed
by some tumor cells, and serious side effects. Those problems create a demand for new
compounds more active against cancer and less toxic to patient. In this context, the search for
complexes with other metals that present different cellular targets appeared to circumvent
such problems. The action of platinum complexes occurs preferentially on DNA while the
gold action is related to the inhibition of the enzyme TrxR which participates in intracellular
redox balance. To enhance biological activity of gold complexes we prepared ligands
containing adamantane with heterocyclic ring oxadiazole or thiazolidine and phosphines
(trimethyl or triphenyl) which are present in bioactive substances. The synthesized
compounds were characterized by CHN, 1H and 13C NMR, IR, Raman, TG and X-ray
diffraction for ligands and complex 1 {triphenylphosphin[5-adamantyl-1,3,4-oxadiazole-2-
thiolate(κS)]gold(I)}. All complexes were more active against tumor cells compared to the
free ligands and more efficient and selective than cisplatin for melanoma cell line (B16-F10).
The complex 4 {Triethylphosphine chloride[(metyl-1-adamantane)1,3-thiazolidine-2-
thione(κS)]gold(I)} showed IC50 values near Auranofin [2,3,4,6-tetra-o-acetyl-1-thio-β-Dglycopyranosate-
trietylphosphingold(I)] and higher selectivity. The ability to inhibit TrxR
was most relevant for the complexes with ethyl phosphine reaching the inhibition promoted
by Auranofin. We have observed a relationship among the capacity to inhibit TrxR, structure
and cytotoxicity which contributes to confirm the mechanism of action for gold compounds.
Thus, this study is an important contribution to the coordination chemistry of gold(I)
complexes.
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Síntese de derivados adamantóides diaminados e amino álcoois, potenciais agentes farmacológicosBarbosa, Gisele 11 July 2014 (has links)
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Previous issue date: 2014-07-11 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Compostos adamantóides têm sido alvo de interesse desde a virada do século 20,
devido a sua analogia com a estrutura do diamante. A estrutura única do adamantano é
refletida em suas propriedades físicas e químicas altamente diferenciadas, que podem
ter muitas aplicações, incluindo a concepção de medicamentos e carreação de fármacos.
Estes estão presentes numa grande variedade de compostos bioativos, mostrando
atividade contra alguns agentes infecciosos e em muitos distúrbios fisiológicos.
Juntamente com as aminas e, principalmente, as poliaminas que são substâncias que
ocorrem amplamente em materiais biológicos podendo estar envolvidas em muitos
aspectos como crescimento, divisão e diferenciação celular, os compostos adamantóides
são considerados um alvo potencial para a quimioterapia de várias doenças,
principalmente as infecciosas. Nesse contexto, esse trabalho tem como proposta a
preparação de novos derivados adamantóides diaminados e amino álcoois, que sejam
potenciais agentes farmacológicos. Para obtenção dos compostos almejados, o 1-
adamantano metanol teve o grupo hidroxila transformado em um melhor grupo
abandonador e em seguida substituído por diferentes aminas e amino álcoois. E, para a
síntese dos derivados da 2-adamantanona foi realizada a aminação redutiva da mesma
com as diaminas e amino álcoois utilizados. Obteve-se 19 compostos, sendo 12 inéditos,
os quais foram caracterizados por espectroscopia na região do Infravermelho e
Ressonância magnética nuclear de 1H e 13C. Foram realizados diferentes ensaios
biológicos e o composto 7 apresentou maior destaque nos testes realizados. / Adamantoids compounds have been the subject of interest since the turn of the
20th century due to its analogy with the diamond structure. The unique structure of
adamantane is reflected in their highly differing physical and chemical properties, which
can have many applications, including drug design and drug delivery, and is present in a
variety of bioactive compounds showing activity against several infectious agents, and
in many physiological disorders. Along with amines and especially polyamines which
are substances that widely occur in biological material may be involved in many aspects
such as growth, cell division and differentiation been considered a potential target for
chemotherapy for several, especially infectious diseases. In this context, this paper aims
at the preparation of new diamines and amino alcohols adamantoids derivatives, which
are potential pharmacological agents. To obtain the desired compounds, 1-adamantane
methanol has the hydroxyl group converted into a better leaving group, and then
replaced by different amines and amino alcohols. For the synthesis of the 2-
adamantanone derivatives it was employed reductive amination with diamines and
amino alcohols followed by the reduction with NaBH3CN. It was prepared in this work
19 compounds, including 12 previously unpublished, which were characterized by
infrared spectroscopy and 1H and 13C nuclear magnetic resonance. Preliminary
biological evaluations were performed and compound 7 showed the best activity on the
realized biological assays.
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Syntéza a charakterizace pokročilých molekul s implementovaným adamantanovým skeletem / Synthesis and characterisation of advanced molecules with implemented adamantane skeletonJančík, Ján January 2018 (has links)
This diploma thesis describes synthetic approach and characterization of advanced molecules with implemented adamantane skeleton and perspective use in attractive field of organic electronics. Three of four prepared molecules based on para-bis(2-thienyl)phenylene are original and totally new, and there were performed different synthetic approaches with comparison of yield, ecological and financial impact. Study of microwave synthetic approach was provided for cross-coupling reactions on para-bis(2-thienyl)phenylene skeleton. For all molecules were used ethyladamantyl and methyladamantyl substituents. Also, two completely new molecules based on 2,2':5',2''-terthiophene with ethyladamantyl and methyladamantyl substituents were prepared. In the next part were prepared new dimer structures of adamantane with possible application on field of polymers as bridge molecules. In the thesis were also made series of experiments for preparation of tetrasubstituted adamantane molecules, and for optimisation of preparation of spiroadamantane systems.
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Modifikace organických vysoce výkonných pigmentů pro aplikace v organické elektronice / Modification of Organic High Performance Pigments for Applications in Organic ElectronicsCigánek, Martin January 2020 (has links)
Dizertační práce pojednává o studiu, syntéze a chemické derivatizaci molekul spadajících do skupiny organických vysoce výkonných pigmentů a jejich potenciálním uplatnění v oblastech organické elektroniky. Teoretická část práce je zaměřena na nejnovější trendy v dané oblasti, a to jak z aplikačního potenciálu konkrétních derivátů, tak z pohledu syntetických možností a jejich strukturálních derivatizací. V experimentální části je pak podrobně popsána příprava pestré škály intermediátů a výsledných produktů, zahrnujících deriváty diketopyrrolopyrrolů (DPP), benzodifuranonu (BDF), epindolidionu (EP), naphthyridinedionu (NTD) a polymeru na bázi thiofenu (PT). Celkově bylo nasyntetizováno 103 molekul, přičemž 49 tvořily výsledné produkty, z nichž 27 bylo zcela nových, dosud nepublikovaných. Hlavním motivem derivatizace molekul pigmentů je zde inkorporace derivátů adamantanu do finálních struktur. V další části práce jsou blíže diskutovány jednotlivé chemické modifikace vedoucí k výsledným produktům. Na sérii N,N'-; N,O'- a O,O'-substituovaných derivátů DPP je popsána komplexní studie vlivu charakteru alkylových řetězců a také pozice jejich navázání v molekule DPP, a to nejen na selektivitu reakce, ale rovněž na optické i termické vlastnosti syntetizovaných produktů.
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Modifikace polypropylenu reaktivním kompaundováním / Modification of Polypropylene by Reactive CompoundingSvítil, Jan January 2018 (has links)
Knowledge of radical initiated grafting was summarized in theoretical part. It also contains a part about adamantane, its derivatives and a study of their use in polymer chemistry. In experimental part radical grafted polypropylene was prepared in batch mixer Brabender at 185 and 195 °C, 40 RPM and reaction time 5 min. Initiator 2,5-dimethyl-2,5-bis(tert-buthylperoxy)hexane (Trigonox 101) in concentrations between 0,2 – 4 wt % was used. 1-vinyladamantane was chosen as a monomer and its concetration ranged from 0,75 to 2,24 wt %. Mechanical properties of prepared samples were tested. Sample with content of initiator 0,2 wt % and monomer 1,4 wt % showed increase in notch toughness by 56,3 %, strength by 8,7 %, ductility by 11,5 % and decrease in MFR (230 °C; 2,16 kg) by 29,7 %. Values of torque indicated grafting reactions which couldn’t be proven by use of FTIR method so more suitable methods have been proposed.
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Protein-Glycopolymer Biohybrid Structures Based on Molecular Recognition Processes for Biomedical ApplicationsEnnen, Franka 11 December 2014 (has links)
The design of versatile biohybrid nanosized materials has revealed itself as a promising avenue towards biomedical applications in today´s life sciences. In this regard the combination of components of synthetic and natural origin facilitates an applicability which is supposed to be far beyond the sum of their single components. These biohybrid structures (BHS) can be built by a huge variety of building blocks including solid or soft nanoparticles, peptides/proteins, polynucleotides or low molecular weight drugs. Along with the latter the attachment of biologically active entities or imaging moieties, e. g. enzymes, fluorescence markers or targeting motifs display thereby a key step towards the development of carrier systems for drug delivery purposes.
Among the soft nanoparticles especially dendritic polymers such as perfectly branched dendrimers or hyperbranched polymers are considered as ideal building blocks, since they allow an easy tailoring of crucial properties such as solubility, biocompatibility or bioactivity by means of surface functionalization. Especially in the field of targeted drug delivery the crucial role of sizes and size distributions of carriers has been highlighted recently, since it critically influences important factors such as circulation time or biodistribution within the body.
The ability of avidin to form high molecular weight associates with biotinylated macromolecules as well as its inherent properties makes it a suitable candidate for passive and active targeting in combination with biotinylated (bio-)polymers. Furthermore, along with the covalent attachment of bioactive moieties, non-covalent attachment is a frequently used approach, because it is assumed to only require stoichiometric mixing. In context of the latter molecular recognition processes such as the avidin-biotin, β-cyclodextrin-adamantane or Ni(II)-NTA-histidine-tag interactions have shown to be fruitful strategies for the attachment of bioactive entities.
The overall aim of this work was to fabricate BHS based on dendritic glycopolymers with varied sizes in the nano- and micrometer range as models for biomedical applications e. g. carriers for drug delivery. Therefore the molecular recognition of avidin with biotin derivatives and β-cyclodextrin with adamantane derivatives was utilized in order to tailor final sizes, functionality or catalytic activity of those BHS.
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Synthesis of Aza- and α,α-disubstituted Glycinyl peptides and application of their electronic and steric interactions for controlling peptide folding, and for biomedical applicationsMohammadpourmir, Fatemeh 01 1900 (has links)
No description available.
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Synthèse par « Click Chemistry » de matériaux hybrides et éudes de leurs assemblages supramoléculaires / Synthesis of hybrid materials via "click-chemistry" and studies of their supramolecular assembliesLe ho, Khanh hy 15 November 2012 (has links)
L’approche « bottum-up » via l’auto-assemblage moléculaire est considéré comme une voie prometteuse pour contrôler la fabrication de nouveaux matériaux et leur intégration dans des dispositifs hybrides présentant de propriétés nouvelles. Dans ce travail, nous avons synthétisé plusieurs hybrides à base de molécules organiques (fullerène, porphyrines, phtalocyanine), d’oligonucléotides ou de nanotubes de carbone.Dans un premier temps, nous nous sommes intéressés à la synthèse d’une nouvelle famille de produits constituée d’une unité C60 lié à deux chromophores positionnés face à face et permettant la formation de complexes hôte-invités. Nous avons montré que ces composés s’assemblent pour donner des structures supramoléculaires en solution et sur surface. Les interactions électroniques et la compléxation entre le fullerène et les deux chromophores (porphyrines et phtalocyanines) ont été étudiées par spectroscopie optique et RMN ainsi que par voltammétrie cyclique.Parmi les outils de l’approche « bottom-up », l’ADN a montré son extraordinaire potentiel pour la fabrication d’assemblages bio-dirigés. En effet, la synthèse de matériaux hybrides à base d’ADN permet un contrôle précis (théoriquement à l’échelle d’une base, ~3,4Å) du positionnement des groupements fonctionnels dans un matériau. Dans le but de former des réseaux bi- et tridimensionnels à base d’ADN permettant le positionnement de nano-objets, nous avons synthétisé des hybrides à base d’oligonucléotides et de porphyrines (molécule 2D) ou d’adamantane (molécule 3D). Des édifices supramoléculaires simples ont été réalisés et le travail se poursuit en vue de la réalisation de réseaux fonctionnels.Enfin, dans une dernière partie, nous nous sommes intéressés à la fonctionnalisation des nanotubes de carbone monoparoi (SWNT) avec des chromophores de type porphyrines et phtalocyanines. Alors que les porphyrines présentent une absorption intense presque exclusivement dans le bleu, les phtalocyanines absorbent principalement dans le rouge. Combiner ces deux chromophores à la surface des nanotubes de carbone présente donc un intérêt particulier pour la collecte de lumière car les deux composés absorbent des régions complémentaires du spectre visible. Ce travail ouvre la voie vers l'étude des propriétés optoélectroniques des hybrides à base de nanotubes et en particulier leur utilisation pour la conversion d’énergie lumineuse en énergie électrique (application photovoltaïque). / An Approach "bottum-up" via molecular self-assembly is considered as a promising way to control the manufacture of new materials and their integration into hybrid devices with novel properties. In this work, we have synthesized several hybrids based on organic molecules (fullerene, porphyrin, phthalocyanine), oligonucleotides or carbon nanotubes.At first, we were interested in the synthesis of a new family of products consisting of a unit C60 linked to two chromophores positioned face to face and allowing the formation of host-guest complexes. We have shown that these compounds are combined to give supramolecular structures in solution and on the surface. Electronic interactions and complexation between fullerene and the two chromophores (porphyrins and phthalocyanines) were studied by NMR and optical spectroscopy as well as cyclic voltammetry.Among the tools of the "bottom-up", DNA showed its tremendous potential for the production of bio-directed assembly. Indeed, the synthesis of hybrid materials based DNA allows precise control (theoretically on the scale of a base, ~ 3.4 Å) of the positioning of the functional groups in a material. In order to form networks and bi-dimensional DNA-based for positioning nano-objects, we have synthesized hybrid oligonucleotide-based and porphyrin molecule (2D) or adamantane molecule (3D). Supramolecular structures have been made and this work is ongoing to achieve functional networks.Finally, in a last part, we are interested in the functionalization of single-walled carbon nanotubes (SWNTs) with chromophores like porphyrins and phthalocyanines. While porphyrins exhibit almost exclusively an intense absorption in the blue (around 420-440 nm), phtalocyanines absorb mainly in the red spectral region. Taken together these two chromophores have interesting light harvesting, photophysical and redox properties; the two components will participate independently to increase the overall absorption in the visible range of the solar spectrum. This work opens the route to study the optoelectronic properties of hybrid nanotube and in particular their use for the conversion of light energy into electrical energy (photovoltaic application).
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Molecular Simulations Of Temperature Induced Disorder And Pressure Induced Ordering In Organic Molecular CrystalsMurugan, N Arul 08 1900 (has links)
Crystallographically solids with well defined crystal structures are normally assumed to be highly ordered. However, it is not uncommon to find considerable degree of disorder amongst many of these crystalline substances. Disorder among crystalline substances often arise from the rotational motion which leads to the well known class of plastic crystalline substances. Typically, globular molecules such as methane, carbon tetrachloride or adamantane exhibit plastic crystalline phase with significant amount of orientational disorder. In many other substances, disorder arises from torsional motion as in the case of biphenyl, p- or o-terphenyls, stilbene or azobenzenes. In case of molecules with flexible segment, such as alkanes or surfactants, motion of the terminal methyl group or terminal ethyl group is responsible for the observed disorder. Chapter 1 discusses various aspects of disorder in crystals.
A new pressure induced solid phase of biphenyl is reported at room temperature. Isothermal-isobaric ensemble variable shape simulation cell Monte Carlo calculations are reported on biphenyl at 300K as a function of pressure between 0-4 GPa. The potential proposed by Williams for inter-molecular and Benkert-Heine-Simmons(BHS) for intramolecular interactions have been employed. Different properties indicating changes in the crystal structure, molecular structure, distributions of inter- and intra-molecular energy are reported as a function of pressure. With increase in pressure beyond 0.8 GPa, the dihedral angle distribution undergoes a change from a bimodal to an unimodal distribution. The changes in IR and Raman spectra across the transition computed from ab initio calculations are in agreement with the experimental measurements. It is shown that at pressures larger than 0.8 GPa, competition between inter-molecular interactions with intra-molecular terms v/z., conjugation energy and the ortho-ortho repulsion favors a planar biphenyl due to better packing and consequently a predominant inter-molecular term. The exact value of the transition pressure will depend on the accuracy of the inter- and intra-molecular potentials employed here.
p-terphenyl has been modeled at 300K and atmospheric pressure with different potential models. Modified Fihppini parameters for mtermolecular interactions and BHS potential for inter-ring torsion predict the structure of p-terphenyl reasonably well. Pressure variation calculations are carried out with this combination of inter- and intra-molecular potential. The structure as a function of pressure upto 5 GPa has been compared with experimental structure provided by Puschnig et al. The transformation of functional form
of the potential energy curve (associated with the inter-ring flipping) from W-shaped to [/-shaped form as a function of pressure has been observed. This is in excellent agreement with previous studies of polyphenyls including biphenyl and p-hexaphenyl. The complete planarization of molecules occurs when the pressure range is 1.0 GPa-1.5 GPa.
Molecular simulation of solid stilbene in the isothermal-isobaric ensemble with variable shape simulation are reported. Structure has been characterized by means of lattice parameters and radial distribution functions. Simulations show existence of pedal-like motion at higher temperatures in agreement with the recent X-ray diffraction measurements by Ogawa and co-workers and several others previously. Difference in energy between the major and minor conformers, barrier to conformational change at both the crystallographic sites have been calculated. Temperature dependence of the equilibrium constant between the two conformers as well as the rate of conversion between the con-formers at the two sites have been calculated. These are in agreement with the recent analysis by Harada and Ogawa of non-equilibrium states obtained by rapid cooling of stilbene. Volume and total intermolecular energy suggest existence of two transitions in agreement with previous Raman phonon spectroscopic and calorimetric studies. They seem to be associated with change from order to disorder at the two sites. Ab initio calculations coupled with simulations suggest that the disorder accounts for only a small part of the observed shortening in ethylene bond ength. A Monte Carlo simulation with variable shape simulation cell has been carried out on stilbene. The study attempts to investigate the disorder at various pressures upto 4 GPa. It is seen that the population of minor conformers at sites 1 and 2 decrease with increase in pressure. Population of minor conformers at site 2 decreases to zero by 1.5 GPa. In contrast, the population of minor conformers at site 1 remains finite for the runs reported here. It is seen that the population of minor conformers at site 1 is higher than at site 2 at room temperature which is to be expected on the basis of the activation energies. Associated changes in the unit cell as well as molecular conformation are discussed.
Isothermal-isobaric ensemble Monte Carlo simulation of adamantane has been earned out with variable shape simulation cell. Low temperature crystalline phase and the room temperature plastic crystalline phases have been studied employing the Williams potential. We show that at room temperature, the plastic crystalline phase transforms to the crystalline phase on increase in pressure. Further, we show that this is the same phase as the low temperature ordered tetragonal phase of adamantane. The high pressure ordered phase appears to be characterized by a slightly larger shift of the first peak towards lower value of r in C-C, C-H and H-H rdfs as compared to the low temperature tetragonal phase. Co-existence curve between the crystalline and plastic crystalline phase has been obtained approximately upto a pressure of 4 GPa.
We investigate the equation of state, variation of lattice parameters and the distortion of molecular geometry of low temperature phase of adamantane upto 26 GPa pressure. A rigid and a flexible model of adamantane have been studied using variable shape simulation within the isothermal-isobaric ensemble. Including six low frequency modes obtained from density functional theory carried out on a single-molecule has incorporated the flexibility. These calculations used Becke 3-parameter method and Lee-Yang-Parr electron correlation functional with 6-31G(d) basis set. The simulated equation of state and variation of c/a ratio as a function of pressure are compared with the experimental results. The results are in good agreement with high pressure experiments. Nature of distortion in molecular geometry obtained from the calculation are also in good agreement with the experiment.
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Selektive Halogenierungen unter Phasentransferbedingungen: Mechanistische Untersuchungen und Synthetische AnwendungenLauenstein, Oliver 27 June 2001 (has links)
No description available.
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