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Energy storage: dielectrophores – molecules with non-linear polarizability

Mourokh L., Lazarev P.

Advances in Materials Science

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2017

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Vol. 17, nr 4(54)

14--21

EN

We examine the feasibility of film capacitors based on dielectrics with high non-linear polarizability as energy storage devices. Capacitors with increased energy density can be built by using composite materials with aromatic molecules (high polarizability) and envelope of alkyl tails (high resistivity). We determine the impact of the second order non-linearity onto energy density and translate high energy density requirements into molecular parameters necessary for high-performance capacitors. The relationship of permittivity and molecular polarizability is obtained by means of the non-linear Clausius–Mossotti equation. In order to demonstrate the the selection process for the molecular composition of dielectrophores, we compare several molecules, using quantum chemistry algorithms (Gaussian09). Starting from Langhals perylene (LP), we proceed with the nitrophenyl-perylene having one NH2 group (donor) and one NO2 group (acceptor). We show that, while their linear polarizabilities are comparable, the hyperpolarizabilities differ by several orders of the magnitudes. Two NH2 and NO2 groups can be attached to the nitro-naphthalene-perylene further increasing of the hyperpolarizability. Even larger polarization can be achieved by additional rylene groups increasing the polarizable electronic mass. We demonstrate that with such molecular engineering, capacitors can have the energy density which is attractive for practical applications.

2

Chemia kwantowa w molekularnej optyce nieliniowej

Wielgus M., Kozłowska J., Bartkowiak W.

Wiadomości Chemiczne

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2012

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[Z] 66, 1-2

1-18

EN

We review quantum-chemical methodologies based on simple two- and three- state models for molecular hyperpolarizabilities and two-photon cross-sections. In this article we show that simplified few-state models, obtained from sum -over-states formalism, are important tools for investigations structure-property relationships for various type of đ-conjugated compounds. These relationships are important for rational design of molecules with large nonlinear optical response

3

The three-body effects in interaction induced electric properties of selected hydrogen-bonded systems

Skwara B., Bartkowiak W.

Scientific Bulletin. Physics / Lodz University of Technology

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2006

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Vol. 26

21-27

EN

In the present work the role of the three-body effects in the interaction induced electronic electric properties of the selected hydrogen-bonded systems (trimers of urea, fluoroacetylene and diformamide) has been investigated. The two- and three-body components of interaction-induced dipole moment , polarizability and first-order hyperpolarizability have been calculated at the MP2/aug-cc-pVDZ level of theory. The contribution of the three body terms into the total interaction induced properties as well as the cooperativity of these terms have been analyzed.

PL

W pracy zaprezentowano wyniki obliczeń dwu- i trójciałowych składowych indukowanych oddziaływaniem właściwości optycznych modelowych układów molekularnych tworzących wiązania wodorowe. Analiza prezentowanych rezultatów prowadzi do lepszego zrozumienia tzw. zjawisk kooperatywnych, które jak się wydaje, pełnią istotną rolę w kształtowaniu struktury materiałów molekularnych. Oblicznia statycznych elektronowych własności optycznych oraz ich indukowanych oddziaływaniem odpowiedników wykonano stosując algorytm skończonego pola (FF) na poziomie metody MP2/aug-cc-pVDZ.

4

Modelowanie własności nieliniow optycznych monomerów z ugrupowaniem chromoforowym

Diduch K., Kucharski S.

Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje

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2001

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Vol. 50, nr 23

355-358

PL

Przy użyciu programu obliczeniowego GAUSSIAN 98 przeprowadzone zostały obliczenia kwantowo-chemiczne polaryzowalności [alfa], hiperpolaryzowalności [beta]° oraz momentu dipolowego [mi] dla benzoimidazolowych, bbenzoitazolowych i etylokarbazolowych pochodnych diazowych p-nitroaniliny, sulfatiazolu oraz sulfadiazyny. Najwyżwsze wartości [beta]° otrzymano dla pochodnych etylokarbazolowych (CARB-1) 63,56 10-30 esu, najniższe zaś dla pochodnych benzoimidazolowych (BIM-2) 19,70 10-30 esu. Wykazano wpływ budowy cząsteczki chromoforu zarówno na wielkość drugiej hiperpolaryzowalności jak i wielkości kryterium FOM (figure of merit). Udział wielkości [beta]° w kryterium FOM dla wszystkich chromoforów z wyjątkiem CARB-1 zawiera się w granicach 0,5-5%.

EN

The polarizability [alfa], first hyperpolarizability [beta]° and dipole moments [mi] of benzoimidazoles, benzothiazoles and ethylcarbazoles derivatives of p-nitroaniline, sulfathiazole and sulfadiazine was evaluated by ab initio (GAUSSIAN 98) quantum-chemical calculations. The highest values of [beta]° were obtained for ethylcarbazoles (CARB-1) 63,56 10-30 esu, the lowest results were obtained for benzoimidazole derivatives (BIM-2) 19,70 x 10-30 esu. Basing of the results of the quantum-chemical calculations the influence of the molecular structure of chromofores on hyperpolarizobility and FOM (figure of merit) was discussed. For the chromofore in question the contribution of [beta]° in FOM is in range of 0,5-5%, except for CARB-1.