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Full-Text Articles in Physical Sciences and Mathematics

Optical Characterization Of Fe^{3+} Doped Cds Nanoparticles Synthesized By Wet-Chemical Route, Seyed Mohammad Taheri Otaqsara, Mohammad Hassan Yousefi, Ali Azam Khosravi Jan 2011

Optical Characterization Of Fe^{3+} Doped Cds Nanoparticles Synthesized By Wet-Chemical Route, Seyed Mohammad Taheri Otaqsara, Mohammad Hassan Yousefi, Ali Azam Khosravi

Turkish Journal of Physics

Fe^{3+} doped CdS nanoparticles using Mercaptoethanol as a capping agent were prepared by colloidal wet-chemical method. UV-VIS spectra show that Fe-doping can effectively tune energy band structure, i.e. a large blue shift (\sim 30 nm) with increasing Fe concentration. PL measurement of doped CdS nanoparticles shows an additional emission band at \sim 532 nm, which can be due to radiative transition of dopant level to ground state. X-ray diffraction patterns studies revealed cubic crystal phase. TEM micrographs show a spherical shape and nearly well distribution with an average particle size of \sim 4 nm.


Role Of Metallic Zn And In Additives In The Electrical And Dielectric Properties Of Se_{0.85}Te_{0.15} Glassy Alloy, Jyoti Sharma, Santosh Kumar Jan 2011

Role Of Metallic Zn And In Additives In The Electrical And Dielectric Properties Of Se_{0.85}Te_{0.15} Glassy Alloy, Jyoti Sharma, Santosh Kumar

Turkish Journal of Physics

In this paper we report the effect of metallic Zn and In additives on the electrical and dielectric properties of Se_{0.85}Te_{0.15} glassy system. The temperature and frequency dependence of the dielectric parameters in glassy Se_{0.85}Te_{0.15}, Se_{0.75}Te_{0.15}In_{0.10} and Se_{0.75}Te_{0.15}Zn_{0.10} alloys are studied by measuring capacitance and dissipation factor in the frequency range (1 kHz--5 MHz) and temperature range (300--350 K). Direct current (dc) measurements were also performed in the aforesaid temperature range to assess the dc conduction losses. Results are interpreted in terms of a theoretical model which is based on two electron hopping over a potential barrier and is applicable …


Investigation Of Extremely Low Frequency (Elf) Hot Spots In The College Of Science And Technology, Covenant University, Ota, Marvel Akinyemi, John Kayode, Mojisola Usikalu Jan 2011

Investigation Of Extremely Low Frequency (Elf) Hot Spots In The College Of Science And Technology, Covenant University, Ota, Marvel Akinyemi, John Kayode, Mojisola Usikalu

Turkish Journal of Physics

The presence of Extremely Low Frequency (ELF) from electronic devices such as personal computers, laboratory equipment and television sets in selected laboratories and offices at the College of Science and Technology Building, Covenant University, Ota, Nigeria was characterized using an ELF Detection Meter. The study revealed that exposure to ELF fields could be controlled to the minimum depending on the awareness of the occupant. As with all electromagnetic fields, the ELF field decays rapidly with distance from source or hot spots. The average observed value of ELF in the offices ranged from 3.5 to 5.0 mG. A significant hot spot …


Study Of Differential Cross Section Using Different Bound State Potentials, Ass'ad I. Ass'ad Jan 2011

Study Of Differential Cross Section Using Different Bound State Potentials, Ass'ad I. Ass'ad

Turkish Journal of Physics

In this study, heavy ion reactions of ^6Li + (^{58}Ni, ^{28}Si, ^{12}C) and ^7Li + ^{12}C are studied using different bound state potentials, within the framework of the Distorted Wave Bourn Approximation (DWBA) calculations. Woods-Saxon potential is expressed as the optical potential in the initial and final channels together with a Coulomb potential. The calculations of the angular distributions are found to be in a good agreement with the experimental data. The extracted spectroscopic factors are reasonable.


A Quantum Theory Of The Scattering Of Soft X-Ray From Compton Effect Caused Electron Standing Wave In The Materials, Biswajit Mallick Jan 2011

A Quantum Theory Of The Scattering Of Soft X-Ray From Compton Effect Caused Electron Standing Wave In The Materials, Biswajit Mallick

Turkish Journal of Physics

In the present investigation, low-energy x-rays (


Effective Size And Expansion Energy Of A Bose-Einstein Condensate In A 3d Non-Cubic Optical Lattice, Shemi S. M. Soliman Jan 2011

Effective Size And Expansion Energy Of A Bose-Einstein Condensate In A 3d Non-Cubic Optical Lattice, Shemi S. M. Soliman

Turkish Journal of Physics

This work is devoted to study the temperature dependence of the effective size and expansion energy E_{x,z} of a Bose-Einstein condensate in a 3D non-cubic optical lattice. Correction due to the finite size, interatomic interaction and the deepness of the lattice potential are given simultaneously. The calculated results show that these two parameters increase with the lattice depth or the relative frequency at temperature less than the transition temperature, (T < T_o); yet it has little effect at temperatures higher than the transition temperature (T > T_o). Both the effective size and expansion energy follow a characteristic temperature dependence, i.e. , E \propto(T/T_0)^4 if T < T_0 and , E \propto (T/T_0) if T > T_0. For a 3D non cubic optical potential the effect of …


Analytical Expression For Mode-Coherence Coefficient Of A Uniformly-Distributed Wave Propagating In Different Homogeneous Media, Noor Ezzulddin Naji Jan 2011

Analytical Expression For Mode-Coherence Coefficient Of A Uniformly-Distributed Wave Propagating In Different Homogeneous Media, Noor Ezzulddin Naji

Turkish Journal of Physics

Presented is a derivation of an analytical expression for the mode-coherence coefficients of uniform-distributed wave propagating within different homogeneous media-as in the case of hyperbolic Gaussian beams-and a simple method involving the superposition of two such beams is proposed. The results obtained from this work are very applicable to study and analysis of Hermite-Gaussian beam propagation, especially in the problems of radiation-matter interaction, and laser beam propagation such as employed in free-space and fiber optical communications.


Dynamical Behavior Of Traveling Wave Solutions For The K(2,2) Equation, Lina Zhang Jan 2011

Dynamical Behavior Of Traveling Wave Solutions For The K(2,2) Equation, Lina Zhang

Turkish Journal of Physics

In this paper, we discuss the qualitative behavior of degenerate singular points for the K(2,2) equation. By analyzing the different dynamical behaviors of the singular system and its associated regular system, we come to the conclusion that for the singular system the smoothness property of its orbits, which have intersection point(s) with the singular straight line, will not be destroyed. Meanwhile, the corresponding smooth traveling wave solutions for the K(2,2) equation are obtained.


Resonant Transfer Excitation Followed By X-Ray For Boron-Like Ions, Hassan Ramadan Jan 2011

Resonant Transfer Excitation Followed By X-Ray For Boron-Like Ions, Hassan Ramadan

Turkish Journal of Physics

Theoretical cross sections for resonant transfer excitation followed by x-ray emission (RTEX) are calculated for the collisions of some ions in the series of the Boron-like ions with H_2 as a target. The calculations have been done for C II, N III, O IV, F V, Ar XIV and Fe XXII ions by folding their dielectronic recombination (DR) cross sections over the momentum distribution (Compton profile) of H_2 target gas. Calculations have been performed from both ground and metastable initial states, in LS - coupling, allowing for \triangle n = 0 excitations. In the present work, the RTEX cross sections …


Electrons Trajectories In Electromagnetically Pumped Free Electron Laser With A Constant Reverse Guide Magnetic Field, Ahmad Omar Jan 2011

Electrons Trajectories In Electromagnetically Pumped Free Electron Laser With A Constant Reverse Guide Magnetic Field, Ahmad Omar

Turkish Journal of Physics

An exact solution to the quartic equation in the wiggler frequency \omega_w, which represents the dispersion relation for this system, is obtained. The effects of the frequency of the wiggler \omega_w on the electron's velocities (v_{\vert \vert} and v_w) are investigated. The regions of interest for the allowed wiggler frequency \omega_w for both group I and group II electron trajectories are discussed.


Strong Optical Injection Locked Semiconductor Laser For High Bit Rate Chaotic Optical Communications, Muzahim Ibrahim Azawe, Ragaad Habib Saied Jan 2011

Strong Optical Injection Locked Semiconductor Laser For High Bit Rate Chaotic Optical Communications, Muzahim Ibrahim Azawe, Ragaad Habib Saied

Turkish Journal of Physics

We present in this article how strong optical injection can produce chaotic dynamics in the output of the semiconductor laser that is preferable for perfect encrypted optical communication networks. Significant increase in the relaxation resonance frequency was found implying higher degree of enhancement in modulation bandwidth. Numerical investigations under the condition of strong optical injection locking of the slave laser shows that instabilities in the photon number was observed and had settled down after a time of in the order of carrier lifetime. The model presented can be used to extract the characteristic parameters of the injection locking for detuning …


2n-Dimensional At Fujii Model Instanton-Like Solutions And Coupling Constant's Role Between Instantons With Higher Derivatives, Mehmet Keçeci̇ Jan 2011

2n-Dimensional At Fujii Model Instanton-Like Solutions And Coupling Constant's Role Between Instantons With Higher Derivatives, Mehmet Keçeci̇

Turkish Journal of Physics

An instanton-like solution is considered for a class of two-dimensional conformal model with Liouville term. The model expressed here is a new higher-dimensional model with scalar-spinor interaction on even-dimensional spaces, and is a generalization of the even-dimensional Fujii model. A recurrence relation for the Fujii model and coupling constant's indices between relations with interaction constant is extracted. The behavior of Gürsey, Akdeniz-Smailagi' c and Fujii coupling constants in 4-dimensional conformal models are examined.


Metals And Metal Oxides Particles Produced By Pulsed Laser Ablation Under High Vacuum, Khurram Siraj, Yasir Sohail, Aasma Tabassum Jan 2011

Metals And Metal Oxides Particles Produced By Pulsed Laser Ablation Under High Vacuum, Khurram Siraj, Yasir Sohail, Aasma Tabassum

Turkish Journal of Physics

A pulsed KrF Excimer laser (248 nm, 15 mJ) was utilized to synthesize different particles on (111) Si substrate under vacuum \sim 10^{-6} torr using Aluminum (Al), Platinum (Pt), Tungsten (W), Molybdenum (Mo), Cadmium Oxide (CdO), and Yttrium Oxide (Y_2O_3) targets. Scanning electron microscope (SEM) was used to study particle size distribution on silicon substrate. The size of individual metal particles was found to be ranging from 71 nm to 2 \mu m whereas metal oxides particles were found in the range of 71 nm to 1.1 \mu m. The particles below 100 nm are formed by gas phase condensation …


Influence Of Doping And Heat Treatments On Carriers Mobility In Polycrystalline Silicon Thin Films For Photovoltaic Application, Beddiaf Zaidi, Bouzid Hadjoudja, Houda Felfli, Allaoua Chibani Jan 2011

Influence Of Doping And Heat Treatments On Carriers Mobility In Polycrystalline Silicon Thin Films For Photovoltaic Application, Beddiaf Zaidi, Bouzid Hadjoudja, Houda Felfli, Allaoua Chibani

Turkish Journal of Physics

In this work, we investigate the influence of doping as well as heat treatments on the mobility of the carriers in polycrystalline silicon layers. It was found that any increase in both parameters leads to an increase in the mobility of the carriers. Such mobilities were shown to be higher in boron doped layers that those doped with arsenic. Moreover, for strong arsenic doping, after the initial increase, we observed a saturation region followed by a final decrease of carrier mobility.


Characteristics Cd_{0.3}Sn_{0.7}Se Thin Films As Absorber Materials For Solar Cell Devices, Salma Mahdi Shaban, Raad Mohammad Saleh, Ahmed Saleh Ahmed Jan 2011

Characteristics Cd_{0.3}Sn_{0.7}Se Thin Films As Absorber Materials For Solar Cell Devices, Salma Mahdi Shaban, Raad Mohammad Saleh, Ahmed Saleh Ahmed

Turkish Journal of Physics

Cadmium Tin Selenide compound Cd_{0.3}Sn_{0.7}Se was prepared by direct reaction of high-purity elemental Cadmium, Tin and selenium. Cd_{0.3}Sn_{0.7}Se thin films were prepared on to well-cleaned glass substrates by vacuum thermal evaporation technique at room temperature of different thicknesses. The X-ray diffraction studies revealed that all the deposited films are amorphous in nature and exhibiting polycrystalline structure when are annealed at 348 K and 373 K. The crystallites were found to have a preferred orientation along the (111) direction. The analysis of its optical characteristics indicated the ability of these films to absorb the visible light due to its graded energy …


Effect Of Cdcl_2/Annealing On The Crystalline Transformation Of Cdte Thin Films Grown By Evaporation At A Low Substrate Temperature, İsmai̇l Polat, Sali̇h Yilmaz, Emi̇n Bacaksiz, Mustafa Altunbaş, Murat Tomaki̇n Jan 2011

Effect Of Cdcl_2/Annealing On The Crystalline Transformation Of Cdte Thin Films Grown By Evaporation At A Low Substrate Temperature, İsmai̇l Polat, Sali̇h Yilmaz, Emi̇n Bacaksiz, Mustafa Altunbaş, Murat Tomaki̇n

Turkish Journal of Physics

The structural and optical properties of CdTe thin films prepared at a low substrate temperature were investigated before and after the CdCl_2/annealing. The crystal structure of CdTe film was cubic with a strong (111) preferential orientation. Annealing at 400 °C without CdCl_2 treatment results in a decrease in the (111) peak intensity while the intensities of the (220), (311) and (331) peaks appeared, indicating that the texture is significantly changed. However, after the CdCl_2/annealing, the film exhibited a hexagonal phase as a dominant structure. The scanning electron microscopy patterns showed that the as-deposited and annealed samples had almost the same …


Hydromagnetic Thermal Boundary Layer Flow Of A Perfectly Conducting Fluid, Kalidas Das Jan 2011

Hydromagnetic Thermal Boundary Layer Flow Of A Perfectly Conducting Fluid, Kalidas Das

Turkish Journal of Physics

Using successive approximation technique, an analysis of unsteady hydromagnetic boundary layer flow with thermal relaxation of perfectly conducting, viscous incompressible fluid past a semi-infinite porous plate in presence of heat absorbing sinks is carried out. The expression for velocity and temperature fields, local skin friction coefficient, local heat transfer coefficient etc have been derived when the free stream velocity exponentially depends on time. The effects of different parameters entering into the problem are shown graphically and discussed numerically.


Electronic Structure Of The Ge And Se Vacancies In Gese Layered Semiconductor, Zakir Jahangirli Jan 2011

Electronic Structure Of The Ge And Se Vacancies In Gese Layered Semiconductor, Zakir Jahangirli

Turkish Journal of Physics

We report the results of a theoretical investigation of electronic properties of ideal cation and anion vacancies in GeSe. The calculations have been performed using self-consistent Green's function method. The bulk electronic structure is described by a tight-binding Hamiltonian in the bases sets of Linear Combinations of Atomic Orbitals (LCAO). The Green's function of the perfect crystal evaluated using an eigenfunction expansion employing wave functions and band structures obtained from a self-consistent, pseudopotential, local-density-functional calculation. The defect potential is calculated using occupied electron states of the perturbed system. Results are obtained in terms of vacancy bound states, vacancy resonances, and …


A High Luminosity Erl On Ring E^-E^+ Collider For A Super Charm Factory, Erdal Recepoglu, Saleh Sultansoy Jan 2011

A High Luminosity Erl On Ring E^-E^+ Collider For A Super Charm Factory, Erdal Recepoglu, Saleh Sultansoy

Turkish Journal of Physics

A high luminosity energy recovery linac-on-ring type electron-positron collider operating as super charm factory is proposed. It is shown that a luminosity above L = 10^{35}cm^{-2}s^{-1} can be achieved for center of mass energy \sqrt{s}=3.77 GeV. The physics goals of this machine in investigation for charmed particles properties are briefly discussed.


Effects Of Deformation Ratio On The Mechanical Properties And Microstructures Changes In An Al-Mg-Si Alloy, Hichem Farh, Rebai Guemini, Serradj Fares, Karim Djemmal Jan 2010

Effects Of Deformation Ratio On The Mechanical Properties And Microstructures Changes In An Al-Mg-Si Alloy, Hichem Farh, Rebai Guemini, Serradj Fares, Karim Djemmal

Turkish Journal of Physics

An investigation has been done to study the effect of deformation ratio and two-step ageing treatment on the microstructure and the mechanical properties in an Al-Mg-Si aluminum alloy. Transmission electron microscopy is used in order to follow the distribution and the morphology of the hardening precipitates. The hardness of the alloy increases with the increasing deformation ratio. The maximum of hardness increases and is shifted to low time with an increase of the deformation ratio. The density of precipitates is more increased and the precipitates become more inhomogeneously distributed when the deformation combines with two-step ageing treatments.


Role Of Quadrupole Deformation In Proton Emitting Nuclei In The Medium Mass Region, Chandrasekaran Anu Radha, Velayudham Ramasubramanian, Emmanuel James Jebaseelan Samuel Jan 2010

Role Of Quadrupole Deformation In Proton Emitting Nuclei In The Medium Mass Region, Chandrasekaran Anu Radha, Velayudham Ramasubramanian, Emmanuel James Jebaseelan Samuel

Turkish Journal of Physics

Nuclear structural studies at and beyond the proton drip line is done with the help of proton radioactivity. It is found that nuclei are not necessarily always spherical. The aim of the present work is to study the role of quadrupole deformation in proton rich nuclei, particularly with respect to odd Z nuclei within the region 50 < Z < 80 near the proton drip line. The deformation is studied using triaxially deformed cranked Nilsson Strutinsky method with tuning. Some of the nuclei in the medium mass region are found to be proton emitters from the ground state with appreciable deformation. Nuclei with 62 < Z < 67 shows considerable deformation that kindled the probability of instability within the nuclei. Significant ground state deformed shapes are observed in the 67 < Z < 73 region.


Phonon Transmission Via Nanojunctions In Bcc Waveguides, Ouahiba Nafa, Boualem Bourahla, Rachid Tigrine Jan 2010

Phonon Transmission Via Nanojunctions In Bcc Waveguides, Ouahiba Nafa, Boualem Bourahla, Rachid Tigrine

Turkish Journal of Physics

Coherent and ballistic phonon transport via nanojunctions between bcc lattices is presented. The model system A/B/A consists of a finite number of bcc atomic layers of an element B sandwiched between two bcc semi-infinite crystals of another element A. The matching method theoretical approach is used to study the dynamical properties of the bcc sandwich system. A calculation is presented for the coherent reflection and transmission scattering probabilities of the system phonons, as elements of a Landauer type scattering matrix. The scattering and transmission spectra via the nanojunctions are analyzed as a function of the incident frequency per propagating mode …


Computations Of Ultrasonic Parameters Of Lanthanide Metals Ti, Zr And Hf, Pramod Kumar Yadawa, Dharmendra Kumar Pandey, Devraj Singh, Raja Ram Yadav, Giridhar Mishra Jan 2010

Computations Of Ultrasonic Parameters Of Lanthanide Metals Ti, Zr And Hf, Pramod Kumar Yadawa, Dharmendra Kumar Pandey, Devraj Singh, Raja Ram Yadav, Giridhar Mishra

Turkish Journal of Physics

The ultrasonic properties in the hexagonal structured lanthanide metals Ti, Zr and Hf have been studied at room temperature. The higher order elastic constants have been calculated for these metals using Lennard-Jones Potential for evaluating orientation-dependent ultrasonic properties. An anomalous behaviour in orientation dependent velocity is obtained, which is due to the combined effect of second order elastic constants and density. The achieved ultrasonic properties are compared with known physical parameters to differentiate them from third group nitrides/laves phase compounds.


Sublimation Of Graphite In Continuous And Pulsed Arc Discharges, Afshan Ashraf, Kashif Yaqub, Sumera Javeed, Sumaira Zeeshan, Rahila Khalid, Sohail Ahmad Janjua, Shoaib Ahmad Jan 2010

Sublimation Of Graphite In Continuous And Pulsed Arc Discharges, Afshan Ashraf, Kashif Yaqub, Sumera Javeed, Sumaira Zeeshan, Rahila Khalid, Sohail Ahmad Janjua, Shoaib Ahmad

Turkish Journal of Physics

Sublimation of graphite has been investigated in continuous and pulsed arc discharges. The results of continuous arc discharge between graphite electrodes are compared with pulsed arc discharge between cylindrical Aluminum cathode and annular graphite anode. The sublimed species include monoatomic and diatomic carbon clusters with their relative composition depending upon the mechanism of energy dissipation in graphite electrodes. Diatomic carbon (C_2) is the dominant subliming cluster. Emission spectroscopy of the Swan band system [d^3\prod _g -a^3\prod _u ] of C_2 has been used to investigate the thermodynamic state and to deduce the vibrational temperature (T_{vib}). The vibrational level densities indicate …


Chemical Bath Deposition And Characterization Of Cu_2o-Cu_Xs Thin Films, D. D. O. Eya Jan 2010

Chemical Bath Deposition And Characterization Of Cu_2o-Cu_Xs Thin Films, D. D. O. Eya

Turkish Journal of Physics

Cu_2O-Cu_xS thin films have been deposited on glass substrate by chemical bath deposition technique. The films were obtained by depositing Copper Sulphide (Cu_xS) on Copper (I) Oxide (Cu_2O) and then Cu_2O on Cu_xS. The peak solar transmittance across the thin films were found to be


Vibration Spectra Of Polar Mixing Optical Phonon States And Fröhlich Electron-Phonon Coupling Behaviors In A Wurtzite Zno Quantum Dot, Li Zhang Jan 2010

Vibration Spectra Of Polar Mixing Optical Phonon States And Fröhlich Electron-Phonon Coupling Behaviors In A Wurtzite Zno Quantum Dot, Li Zhang

Turkish Journal of Physics

Based on the dielectric continuum model and Loudon's uniaxial crystal model, the interface-optical-propagating (IO-PR) mixing phonon states of a quasi-zero-dimensional (Q0D) wurtzite cylindrical quantum dot (QD) are investigated. It is found that there are two types of IO-PR mixing phonon modes, i.e. \rho-IO/z-PR mixing modes and the z-IO/\rho-PR mixing modes coexisting in Q0D wurtzite QDs. Numerical calculation on a wurtzite ZnO QD shows that the dispersion frequencies of the mixing modes are discrete functions of the azimuthal quantum number and axial wave-number. The calculated results agree well with the recent experimental spectra in ZnO QDs. An abnormal electron-phonon coupling strength …


Inept Nmr Spectroscopy Of ^{14}Nd_N Groups: Product Operator Theory And Simulation, Deni̇z Türkpençe, İrfan Şaka, Azmi̇ Gençten Jan 2010

Inept Nmr Spectroscopy Of ^{14}Nd_N Groups: Product Operator Theory And Simulation, Deni̇z Türkpençe, İrfan Şaka, Azmi̇ Gençten

Turkish Journal of Physics

Product operator formalism is widely used for the analytical description of multi-dimensional and multiple-pulse NMR experiments for the weakly coupled spin systems having spin-1/2 and spin-1 nuclei. The INEPT NMR experiment is a polarization transfer experiment including J-coupling. In this study, the INEPT NMR experiment was analytically investigated by using product operator theory for weakly coupled IS_n(^{14}ND_n) (I=1, S=1; n=1, 2, 3) spin systems. The obtained theoretical results represent the FID values of ^{14}ND_n groups. In order to make Fourier transform of the obtained FID values, a Maple program is used and then simulated spectra of the INEPT experiment are …


On The S-Wave Jost Solution For Coulomb-Distorted Nuclear Potential, Ujjwal Laha, Bibekananda Kundu Jan 2010

On The S-Wave Jost Solution For Coulomb-Distorted Nuclear Potential, Ujjwal Laha, Bibekananda Kundu

Turkish Journal of Physics

A closed form expression of the off-shell Jost solution for Coulomb plus separable nuclear potential is derived using interacting Green's functions and their integral transforms. As an application of our result the off-shell Jost function for the proton-proton scattering in the ^1S_0 channel is computed for various laboratory energies to investigate the role of long range Coulomb interaction in off-shell scattering.


The Investigation Of Hardness And Bonding Behavior In Xb_4, X = {Ce, Th, U, Pa}, Tetraborides By First-Principles, Sezgi̇n Aydin, Aynur Tatar Jan 2010

The Investigation Of Hardness And Bonding Behavior In Xb_4, X = {Ce, Th, U, Pa}, Tetraborides By First-Principles, Sezgi̇n Aydin, Aynur Tatar

Turkish Journal of Physics

The mechanical and electronic properties of XB_4, X = {Ce, Th, U, Pa}, tetraborides have been studied by using first-principles based on density functional theory. The results show that these boron-rich solids are mechanically and thermodynamically stable. From the calculated band structure and density of states, we obtained that they have metallic character. When the calculated parameters related to the crystal structure were considered with the bonding characteristics, the microscopic hardnesses of these boron-rich solids can be theoretically calculated. The obtained hardness values indicate that, these materials are hard, but not superhard. Furthermore, from the detailed hardness analysis, we found …


Electron Paramagnetic Resonance Study Of Vo^{2+} Doped Single Crystal Of Ferroelectric Guanidinium Uranyl Sulphate Trihydrate, Mohammad Imtiazul Haque, Mohammad Umar Jan 2010

Electron Paramagnetic Resonance Study Of Vo^{2+} Doped Single Crystal Of Ferroelectric Guanidinium Uranyl Sulphate Trihydrate, Mohammad Imtiazul Haque, Mohammad Umar

Turkish Journal of Physics

We report result obtained from an EPR study of vanadyl ion (VO^{2+}) in a single crystal of ferroelectric guanidinium uranyl sulphate trihydrate. The Spin-Hamiltonian parameters were also determined via EPR data. VO^{2+} enters the lattice interstitially at two distinguishable sites and resulting vanadyl complexes have nearly axial symmetry.