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1

The effect of the dipole moment on hole conductivity of polycrystalline films of two anthracene derivatives

Kania S., Kościelniak-Mucha B., Kuliński J., Słoma P., Wojciechowski K.

Scientific Bulletin. Physics / Lodz University of Technology

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2017

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Vol. 38

27--36

EN

Hole mobility in the polycrystalline layers of anthrone and anthraquinone differs in one order of magnitude in spite of nearly the same crystalline structure. The origin of this difference was determined with use of the quantum-mechanical calculations carried out at the density functional theory level using the B3lYP functional in conjunction with the 6-311++G(d,p) basis set. Based on theses calculations, we suppose that these difference can result from the presence of the dipol moment in the anthrone molecules.

PL

Ruchliwości dziur w polikrystalicznych warstwach antronu i antrachinonu różnią się prawie o jeden rząd wielkości, pomimo niemal tej samej struktury krystalicznej. Źródło tej różnicy próbowano określić przy użyciu obliczeń kwantowo-mechanicznych przeprowadzonych na poziomie teorii funkcjonału gęstości (DFT) z wykorzystaniem funkcjonału B3LYP, stosując funkcje bazy 6-311++G(d,p). Na podstawie tych obliczeń przypuszczamy, że ta różnica jest wynikiem obecności momentu dipolowego w cząsteczkach antronu.

2

The effect of symmetry of a molecule electronic density on the dipolemoment of unit cell and hole conductivity of thin polycrystalline films of anthrone and anthraquinone

Kania S., Kościelniak-Mucha B., Kuliński J., Słoma P., Wojciechowski K.

Scientific Bulletin. Physics / Lodz University of Technology

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2016

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Vol. 37

49--64

EN

The electronic structure of anthrone and anthraquinone molecules in the gas state and in the simulated crystal unit cell were calculated with time dependent-density functional theory (TD-DFT) method. The values of dipole moment of single molecule and of single crystal unit cell were also determined with TD-DFT method. The results of TD-DFT were compared with known crystal structures of both compounds [1,2]. For both molecules it was observed improvement of matching the length of corresponding bonds when calculated for the unit cell. Unexpectedly high value of dipole moment was calculated for the single unit cell of anthrone. This fact can be responsible for the nano-dimension properties of anthrone as the carriers mobility or high boiling point.

PL

Metodą TD-DFT obliczono strukturę elektronową cząsteczek oraz wartości momentu dipolowego komórek elementarnych dla antronu i antrachinonu. Zaobserwowano wpływ pola krystalicznego na zmianę długości wiązań w szkielecie antracenowym, który to obliczono metodą TD-DFT dla cząsteczek obu związków w fazie krystalicznej. Doświadczalnie określono wpływ obecności momentu dipolowego komórki elementarnej na ruchliwość dryftową nośników ładunków dla dwu aromatycznych związków wielopierścieniowych, antronu i antrachinonu krystalizujących w podobnej sieci krystalicznej C2h5(P21/a), ale różniących się symetrią cząsteczki. W przypadku antronu, posiadającego niecentrosymetryczne cząsteczki, okazało się, że własności tego materiału są związane z jego rozmiarami. Mikroskopowe oddziaływania mające swoje odzwierciedlenie zarówno w wyznaczonej eksperymentalnie bardzo wysokiej temperaturze wrzenia, jak i w wynikach obliczeń momentu dipolowego pojedynczej komórki elementarnej antronu są związane z możliwością zwiększenia aromatyczności cząsteczek tego związku w fazie stałej. Wydaje się, że jest to przyczyną zwiększonej ruchliwości dziur w przypadku antronu w porównaniu do ruchliwości dziur w antrachinonie (o cząsteczkach centrosymetrycznych).

3

Aqueous Solution and Computed Gas Phase Properties of Meclofenamic Acid Sodium Salt

Kharat S.J.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 41

124--131

EN

Paper reports densities, ultrasonic velocities, and refractive indices of aqueous solutions of meclofenamic acid sodium salt (Na-MCF). Densities, ultrasonic velocities, and refractive indices have been measured at (298.15, 303.15, 308.15, and 313.15) K and at atmospheric pressure. Limiting molar volume and limiting molar isentropic compressibility have been calculated. DFT method has been used for computation of dipole moment, free energy, hydration free energy, and HOMO and LUMO energies of Na-MCF. Gas phase properties have been computed by the use of G09 W Software.

4

The magnetic dipole moment of a cellular phone

Yahalom A., Einat M.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 5a

31-33

EN

In the following we measure the magnetic field of a cellular phone. It is found that the magnetic field is comparable to that of the earth's magnetic field at 6,3 cm above the phone. However, the field is not uniform as the earth's magnetic field but bears the unique distribution of a magnetic field induced by a magnetic dipole. The dipole moment is calculated. Recent claims regarding the safety of cellular phones suggest that weak static magnetic fields are induced around the phone, and this field and its gradients may pose a health risk to the user. An experiment was conducted to measure the induced static magnetic field around a cellular phone. 65 žT variations and 18 žT/cm gradients were measured in the magnetic field at about 6 cm from the phone. The influence the measured magnetic fields may have on the user is beyond the scope of this research.

PL

W pracy mierzymy pole magnetyczne od telefonu komórkowego Stwierdzono, że pole magnetyczne telefonu przyjmuje wartości porównywalne z wartościami ziemskiego pola magnetycznego dla odległości około 6,3 cm od telefonu. Jednakże, pole nie ma rozkładu jednostajnego podobnie jak ziemskie pole magnetyczne, lecz wykazuje unikalny rozkład. Wyznaczono moment dipolowy. W najnowszych pracach dotyczących bezpieczeństwa użytkowania telefonów komórkowych twierdzi się, że słabe pola magnetyczne są indukowane wokół telefonu i że pola te mogą stanowić zagrożenie dla użytkownika. Przeprowadzono eksperyment w celu zmierzenia indukowanego statycznego pola magnetycznego wokół telefonu komórkowego. Z pomiarów uzyskano wartości zmienności indukcji na poziomie 65 žT oraz gradienty na poziomie 18 žT/cm dla odległości około 6 cm od telefonu. Określenie wpływu, jaki mogłyby mieć pola o tego typu charakterystyce na użytkownika nie jest przedmiotem rozważań w niniejszej pracy.

5

Elektrooptyczny efekt Kerra w chemii

Prezhdo O., Olan K., Zubkowa W., Preżdo W.

Wiadomości Chemiczne

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2011

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[Z] 65, 1-2

1-31

EN

The electro-optical Kerr effect finds wide application in conformational analysis of molecules and molecular aggregates [1–5], particularly in cases where the standard X-ray and NMR techniques cannot be used. For instance, NMR allows to establish conformations of linear and cyclic unsaturated organic compounds. However, it is less effective in an analysis of molecular complexes, particularly of those that have several rotational symmetry axes. In such cases a combination of techniques based on molecular dipole moments, electro-optical Kerr effect, optical Kerr effect, IR spectroscopy, and Rayleigh scattering can be applied [6]. The foundations of conformational analysis of molecular complexes using several complementary physical approaches are developed in Ref. [7]. The electro-optical methods are particularly useful for an investigation of intramolecular interactions [8–18]. The strength, direction and other details of intramolecular interactions can be determined by analyzing the deviations of the experimental molar Kerr constant (mK) from its value calculated according to the tensor-additive scheme that operates with polarizability tensors of molecular cores and functional groups [19, 20]. For instance, using this approach it has been shown that weakening of conjugation in an electron donor-acceptor chain can lead to flattening of the molecular structure [21]. The Kerr constant is also very sensitive to intermolecular interactions [22–29]. In order to assess quantitatively an extent of the solvent effect on the mK values, both molecular and continuum models of solution structure have been used [30, 31]. The mK values are greatly affected by the mutual orientation of solvent and solute molecules, which interact by dispersive, inductive and dipole-dipole forces [32]. Hydrogen and donor-acceptor bonding have an even stronger influence on the mK values [33]. The equimolar mixtures approach developed in Ref. [34] allows to determine the molar Kerr constant (mK), dipole moment (m), equilibrium constant (K) and, ultimately, structure of a molecular complex based on measurements of the Kerr constant (B), dielectric permittivity (e), density (d) and refractive index (n) of a series of dilute solutions of the complex. Future trends in the development of the electro-optical methods in chemistry are discussed. Theories that relate the electric-optic proprieties of molecules with their reactivity are particularly important. Such theories should be able to predict the changes in the polarizabilities and dipole moments of bonds, molecules and molecular aggregates during the course of chemical reactions.

6

Effect of the Dielectric Medium on the Conformational Behaviour of Methyl 3-Nitrobenzoate

Konopacka A., Kalenik J., Pawełka Z.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 9

1583-1592

EN

Conformational analyses of methyl 3-nitrobenzoate (MNB) was performed, employing DFT, MP2, and semi-empirical quantum-chemical calculations, as well as classical methods based on atomic charge and dipole moment approximations. Properties such as the relative energies of the O-NO2 trans and O-NO2 cis isomers, their populations and dipole moments, all in vacuum, were considered first. Then the conformational trans cis equilibrium was quantitatively established by dipole moment measurements in solvents of dielectric permittivities between 2.016 and 10.34. Different approaches, based on continuum-dielectric and MSAmodels were explored to explain the contribution of the electrostatic interaction to the standard Gibbs energy change delta G° of the trans cis transformation in MNB in solution.

7

The temporal dipole moments of solute molecules undergoing charge transfer

Krzysztofowicz A, Tomin V I

Optica Applicata

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2006

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Vol. 36, nr 4

s. 483--487

EN

The expression for time dependence of excited state dipole moment of molecule with charge transfer on the correlation function of instant spectra kinetics has been deduced on the basis of the theory of solvatochromism. Time dependence of excited state dipole moment of well known luminescence probe 6-propionyl-2-dimethylaminonaphtalene in polar solvent is presented.

8

On calculations of the dipole moment from the electron density data

Gryciuk M., Górecki J.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2002

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Vol. 6, No 4

661-668

EN

In the paper we discuss how to calculate the dipole moment using the electron density data. A few numerical methods are compared. We have found that usually the interpolation of electron density gives the most accurate results.

9

Molecular parameters of some antiferroelectric liquid crystals

Raszewski Z., Rutkowska J., Perkowski P., Zieliński J., Kędzierski J., Piecek W., Kłosowicz S., Żmija J.

Biuletyn Wojskowej Akademii Technicznej

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2002

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Vol. 51, nr 1

21-33

PL

W pracy zbadano dwa związki ciekłokrystaliczne MHPB(H)PBC oraz MHPB(F)PBC wykazujące właściwości antyferroelektryczne, zsyntezowane w WAT. Wyznaczono szereg wielkości charakteryzujących fazę jak: kąt tiltu θ, polaryzację spontaniczną Ps w fazie anty- i ferroelektrycznej. Na podstawie pomiarów optycznych oraz densytometrycznych, korzystając z dwóch różnych procedur ekstrapolacyjnych, obliczono polaryzowalności (αL i αT) molekuł tworzących fazę ciekłokrystaliczną. Wartość momentów dipolowych wyznaczono z pomiarów dielektrycznych w fazie izotropowej (korzystając z równań Maiera - Meiera) oraz z modelowania komputerowego za pomocą programu Hyper Chem 5.0.

EN

Two investigated antiferroelectric liquid crystals, MHPB(H)PBC and MHPB(F)PBC, were synthesized [1] and some their physical properties were described earlier [2]. Apart from the above, MHPB(H)PBC and MHPB(F)PBC have been studied by means of dielectric, densitometric, refractometric and X-ray measurements. Spontaneous polarisation and tilt angle θ in ferro- (SmC*) and antiferroelectric (SmC*A) phases of MHPB(H)PBC and MHPB(F)PBC have also been invastigated. Transverse αT and longitudinal αL molecular polarizabilities have been calculated from the ordinarynO and extraordinary nE refractive indices and densityρ of MHPB(H)PBC and MHPB(F)PBC, using Neugebaure, Vuks and Lorentz wquations with both Haller and Subramhanyama extrapolation procedures. Effective values of the molecular dipole moment have been calculated from electric permittivity in the I phases of these compounds, using Maier and Meier equation.

10

Polarity, Polarizability and Molecular Structure of Autocomplexes on the Basic of 1,4-Naphthoquinone

Prezhdo V.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 10

1521-1531

EN

Experimental and theoretical investigation of molecular dipole moments and molar Kerr constants of 1,4-naphthoquinone based autocomplexes has been carried out. The results indicate the presence of intramolecular charge transfer of the n-_* type. A correlation of the experimental values of molar Kerr constants with the _0-constants of substituents to the arylamine fragment of the autocomplexes has been established. Substituents to the electron donor fragment of the autocomplexes systematically affect the angle between the donor and acceptor fragments. Ab initio quantum-chemical calculations support the n-_*-charge transfer structure and show notable changes in the charge on the nitrogen atom of the donor fragment due to complex formation.

11

Dipole Moment, Molar Kerr Constant, Crystal and Molecular Structure of 3-Chloro-N-methyl-N-nitroaniline

Prezhdo V., Bykova A. S., Głowiak T., Prezhdo O. V., Daszkiewicz Z., Kyzioł J. B.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 5

707-718

EN

Dipole moment, molar Kerr constant, crystal and molecular structure of m- ClC6H4N(CH3)NO2 (or C7H7ClN2O2) are studied. Comparison the data obtained by dipole moment and molar Kerr constant measurement, X-ray crystallographic investigation and quantum-chemical calculation show that the molecule contains a planar NNO2 nitroamino group which is twisted around the N-Cphenyl bond by ca 61.4_ from the plane of the aromatic ring. The structural data are compared with the data for p- ClC6H4N(CH3)NO2 and the influence of the substituent on the structural parameters of the molecule is established.

12

Aromatic Solvent Effect on Polarity and Proton-Transfer Equilibrium in Phenol-Triethylamine Systems

Pawełka Z., Kuc T.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 6

845-855

EN

Dipole moments of hydrogen-bonded complexes of 4-nitrophenol-triethylamine and 2,4,6-trichlorophenol-triethylamine have been determined in various aromatic solvents. On this basis, the Gibbs energy _GPT of the proton-transfer equilibrium has been estimated. The aromatic solvent effect on the proton transfer has been discussed in terms of two solvation contributions, arising from a local complex-aromatic molecules interaction and a long-range dielectric effect. The microstructure of the solvent near a complex has been taken into account, utilizing a dielectric model of two spherical solvent layers. The crucial effect of the size of the aromatic solvent molecules on _GPT has been simulated by variation of the thickness of the first solvation layer.

13

Comparison of the ab-initio calculated and X-ray molecular geometries of the o-, m-, and p-cyanoaniline

Janczak T.

Polish Journal of Chemistry

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1999

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vol. 73 nr 4

655-667

EN

Ab-initio gas-phase structure calculation of the geometry of three isomers of the cyanoaniline were determined using the Hartree-Fock level of theory. The optimized molecular structures have been compared with the in-crystal geometry of the molecules. The small differences in the bond lengths and angles were interpreted and analyzed in terms of the distribution of the charge density. The calculated charge density and its Laplacian function were analyzed in terms of the topological properties at the (3,-1) critical points (CPs) of the covalent and polar bonds. The effect of the donor-/acceptor functional groups attached to the phenyl ring is demonstrated especially in the location of the bond critical points and in the charge density at the bond critical points.

14

Applications of linear and non-linear polarization to conformational equilibria studies

Małecki J., Nowak J.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

210-229

EN

Applications of linear and non-linear dielectric effects to studies of intramolecular equilibria in liquids are described. The physical principles of the two phenomena being responsible for the magnitude of the observed effect, i.e. the Langevin effect and the chemical effect, are outlined. The later effect consists in shifting the molecular equilibria under an influence of electric field to favour the more polar products of reaction. The experimental set-up and its limitations are shortly described. Applications of Non-linear Dielectric Effect (NDE) to determine the changes in free energy, enthalpy and entropy of fast intermolrcular equilibria are described and illustrated by selected examples. The significance of the solvent polarity and its dependence on temperature in enthalpy and entropy is analyzed. Two opposite approaches to calculate these quantities are presented: directly from experomental data according to the usually applied procedure and under the assumption of a constant polarity. Presented experimental results illustrate the physical meaning of these quantities and the significance of the applied approach to the interpretation of experimental results.

15

Ab initio theoretical study of dipole-bound anions of molecular complexes. Water molecule inhibits or enhances electron affinity of N-methylaminoadenine

Smets J., Smith D.M.A., Elkadi Y., Adamowicz L.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 7S

1615-1623

EN

Ab initio calculations have been performed to determine the electron affinity of the water complex of N-methylaminoadenine (NMA). This complex has been chosen for this study because it can form three different isomeric structures with a water molecule hydrogen- bonded at three different NMA sites, and only two of these structures have sufficient dipole moments to form dipole-bound states with an excess electron. In the third structure, which according to the calculations should be the most stable form, the dipole moments of NMA and the water molecule oppose each other resulting in an almost null dipole moment of the complex, so the complex has no ability to form a stable dipole-bound anion. This detrmination offers an interesting possibility for an experimental investigation of whether the NMA x H2O complex forms an stable anion. If such an anion is detected, it will mean that an electron attachment can increase the gas-phase concentration of the complex, which is thermodynamically less stable in its neutral form.