SEMPOZYUM BĐLĐM KURULU SEMPOZYUM DÜZE LEME KURULU

SEMPOZYUM BĐLĐM KURULU Prof Dr Zehra AKDENĐZ Prof Dr Sevim AKYÜZ Prof Dr A Nihat BERKER Prof Dr Bedia Erim BERKER Prof Dr Can Fuat DELALE Prof Dr Gülay DERELĐ Prof Dr Bekir KARAOĞLU Prof Dr Mustafa KESKĐN Prof Dr Ş Erol OKAN Prof Dr Oktay SĐNANOĞLU Prof Dr Yani SKARLATOS Prof Dr Bilal TANATAR Prof Dr Hasan TATLIPINAR Prof Dr Mehmet TOMAK Prof Dr Đskender YILGÖR Prof Dr Ersin YURTSEVER Piri Reis Üniversitesi Kültür Üniversitesi Sabancı Üniversitesi Đstanbul Teknik Üniversitesi Đstanbul Teknik Üniversitesi Yıldız Teknik Üniversitesi Đstanbul Aydın Üniversitesi Erciyes Üniversitesi Trakya Üniversitesi Yale Üniversitesi Boğaziçi Üniversitesi Bilkent Üniversitesi Yıldız Teknik Üniversitesi Ortadoğu Teknik Üniversitesi Koç Üniversitesi Koç Üniversitesi SEMPOZYUM DÜZE LEME KURULU Prof Dr Zehra AKDENĐZ Yrd Doç Dr Ali KARAMAN Yrd Doç Dr Zeynep Çiçek ÖNEM Hanifi ARSLAN Piri Reis Üniversitesi Đstanbul Üniversitesi Đstanbul Üniversitesi Piri Reis Üniversitesi

Sıvıhal Fiziği Çalışma Grubu 13 ULUSAL SIVIHAL FĐZĐĞĐ SEMPOZYUMU 27-29 Ekim 2009 Piri Reis Üniversitesi Konferans Salonu, Tuzla, Đstanbul 27 October/Ekim 2009, Tuesday/Salı 1000-1300 Registration/Kayıt 1015-1030 Opening/Açılış PROGRAM Chairperson/Oturum Başkanı: Zehra Akdeniz 1030-1110 Water: Its Physics, anophysics, Chemistry, and Geopolitics A ihat Berker (Sabancı Üniversitesi) BREAK / ARA 1120-1150 Lanthanide-alkali metal halide systems: characterization and prediction of phase diagram topology Marcelle Gaune Escard, Leszek Rycerz, Slobodan Gadzuric (Ecole Polytechnique, Mecanique Energetique, Technopole de Chateau- Gombert, France) 1150-1220 A-body system problem: on-symmetrized Basis Function for Identical Particles Mario Gattobigio, AKievsky and MViviani ( ice Sophia Antipolis University, France) 1220-1240 Su Damlalarının Su Tutmayan Yüzeyler Üzerindeki Hareketinin Fısıldayan Galeri Modları ile Gözlenmesi Y Karadağ, M Y Yüce, A Kiraz, M Bayındır (Koç Üniversitesi) 1240-1300 Single Wall Carbon anotubes Under Uniaxial Strain Gülay Dereli, ecati Vardar, Önder Eyecioğlu (Yıldız Teknik Üniversitesi) 1300-1320 Density profiles and inertia moments of interacting bosons in anisotropic harmonic confinement A Đ Meşe, P Capuzzi, Z Akdeniz, Ş E Okan (Trakya Üniversitesi)

1330-1430 LU CH/ÖĞLE YEMEĞĐ Chairperson/Oturum Başkanı: Bilal Tanatar 1440-1520 Localization-Delocalization Transition in Ultracold Atomic Mixtures Patrizia Vignolo (Institut on Linéaire de ice, C RS-France) 1520-1540 Multilayered Quantum Wires and Quantum Dots Ş Aktaş (Trakya Üniversitesi) BREAK / ARA 1550-1610 The Binding Energy of the Multilayered Spherical Quantum Dot under a Magnetic Field F K Boz, Ş Aktaş, Ş E Okan (Trakya Üniversitesi) 1610-1630 Density-of-State and Transport Properties for Random Dimer Hamiltonian S Sucu, Ş Aktaş, P Vignolo, Z Akdeniz, ŞE Okan (Trakya Üniversitesi) 1630-1650 Effect of Laser on Quantum Well B Bekar, Ş Aktaş, F K Boz, Ş E Okan (Trakya Üniversitesi) 1650-1710 The multilayered cubic quantum dot under the external fields Özge Kılıçoğlu, Ş Aktaş, F K Boz, Ş E Okan (Trakya Üniversitesi) 28 October/Ekim 2009, Wednesday/Çarşamba Chairperson/Oturum Başkanı: Hasan Tatlıpınar 1030-1110 Water Dynamics in the Hydration Shell of a Protein Cem Servantie (Sabancı Üniversitesi) 1110-1130 Reorientation of Carbon anotubes by Liquid Crystal Mediums S Eren San (Gebze Yüksek Teknoloji Enstitüsü) 1130-1150 Density functional theory study on molecular structure and vibrational spectra of m- methylaniline M Kumru, T Bardakçı, L Sarı (Fatih Üniversitesi)

1150-1210 Optical and Microstructural Properties of Tm 3+ Doped (1-x)TeO 2 -(x)zno- 5TiO 2 Glasses Đdris Kabalcı (Harran Üniversitesi) BREAK / ARA 1220-1250 Simulation of Atomic and Molecular Clusters and Complexes Mustafa Böyükata (Bozok Üniversitesi) 1250-1310 DFT study of titanium-doped boron clusters: TiB n (n=1-9) M Akar, M Böyükata, Z B Güvenç (Bozok Üniversitesi) 1310-1330 Benzene hosting on 4-, 5- and 6-atom cage boron clusters Elmas, M Böyükata, Z B Güvenç (Bozok Üniversitesi) 1330-1430 LU CH/ÖĞLE YEMEĞĐ Chairperson/Oturum Başkanı: Gülay Dereli 1440-1520 Scale Separation in Cavitating Flows Can Fuat Delale (Đstanbul Teknik Üniversitesi) 1520-1550 Lantan Elementinin Aşırı Đnce Yapısının Đncelenmesi Feyza Güzelçimen, Gönül Başar (Đstanbul Üniversitesi) 1550-1620 Feedforward neural network approach to nonlinear optics of nematic liquid crystals ihat Yıldız (Cumhuriyet Üniversitesi) 29 October/Ekim 2009, Thursday/Perşembe 1100-1600 Çalıştay; Aşırısoğuk Atomik Sistemler, Trakya Üniversitesi, Edirne

Water: Its Physics, anophysics, Chemistry, and Geopolitics A ihat Berker Sabancı Üniversitesi

Lanthanide-alkali Metal Halide Systems: Characterization and Prediction of Phase Diagram Topology Marcelle Gaune-Escard 1, Leszek Rycerz 2, Slobodan Gadzuric 3 (1) Ecole Polytechnique, Mecanique Energetique, Technopole de Chateau-Gombert, 5 rue Enrico Fermi, 13453 Marseille Cedex 13, France (2) Chemical Metallurgy Group, Faculty of Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland (3) Faculty of Science, Department of Chemistry, University of ovi Sad, Trg D Obradovica 3, 21000 ovi Sad, Serbia E-mail : marcellegaune-escard@polytechuniv-mrsfr Complex phase equilibria in lanthanide halide-alkali metal halide systems are characterized by the existence of several stoichiometric compounds Their stability depends both on the nature of cations (lanthanide, alkali) and of the halide A simple scheme for classifying phase diagram topology, with predictive capability, is presented

on-simmetryzed Hyperspherical Harmonics basis for A _ 4 system M Gattobigio a, A Kievsky b, and M Viviani b a Universit e de Nice, INLN, 1361 Route des Lucioles, 06560 Valbonne, France (MarioGattobigio@inlncnrsfr) b Istituto Nazionale di Fisica Nucleare, Largo Pontecorvo 3, 56100 Pisa, Italy The Hyperspherical Harmonic (HH) method has been widely used in nuclear physics to describe nuclei with A=3,4 [1] The extension to larger systems is hampered by the large degeneracy of the HH basis The construction of specifically anti-symmetric states reduces the dimensionality of the basis but encounters technical and numerical difficulties The coefficients of anti-symmetric basis elements, constructed as a linear combination of HH basis elements times appropriate spin-isospin vectors, are the more difficult to obtain the larger the number of basis elements and/or the number of particles considered; however, once the basis has been anti-symmetrized, the solution of the Schroedinger equation becomes much easier because the potential energy matrix elements can be calculated efficiently In a preliminary work [2,3] we have discussed the possibility of using the HH method without resorting to the construction of anti-symmetrized basis states, and we have used the proposed formalism to calculate the discrete states of A=3,4 nuclei described by a simple nucleonnucleon potential The obvious disadvantage of the proposed approach lies in the very large basis that one needs to handle, which has to be balanced with the simplicity of avoiding the initial construction of antisymmetric basis states; the physical basis states, having the desired symmetry, are automatically generated in the diagonalization of the Hamiltonian In the present talk we extend the use of non-symmetrized HH basis set to systems made of A = 5, 6 body The growing dimension of the basis set is taken into account by avoiding the explicit construction of the Hamiltonian; we show that the Hamiltonian can be written as a sum of tensor products of sparse matrices These matrices are the transformation coefficients of HH constructed with different sets of Jacobi vectors [4], and the potential energy evaluated on the reference Jacobi set This factorization of the Hamiltonian permits to calculate its action on a vector, that is the basic ingredient for an iterative diagonalization References 1 A Kievsky, S Rosati, M Viviani, LE Marcucci, and L Girlanda, J Phys G: Nucl Part Phys 35, 063101 (2008) 2 M Gattobigio, A Kievky, M Viviani, and P Barletta Phys Rev A 79, 032513 (2009) 3 M Gattobigio, A Kievky, M Viviani, and P Barletta Few-Body Systems 45, 127 (2009) 4 M Viviani, Few-Body Systems 25, 177 (1998)

Su Damlalarının Su Tutmayan Yüzeyler Üzerindeki Hareketinin Fısıldayan Galeri Modları ile Gözlenmesi Yasin Karadağ 1, M Yavuz Yüce 1, Alper Kiraz 1, Mehmet Bayındır 2 1 Koç Üniversitesi, Fizik Bölümü, Sarıyer, Đstanbul 2 Bilkent Üniversitesi, Fizik Bölümü, Çankaya, Ankara Su tutmayan yüzeyler sıvıhal fiziğinde ilgi çeken bir araştırma konusu olmuştur Bu konudaki çalışmaların önemli bir kısmı su tutmama özelliği ile yüzey pürüzlülüğü arasındaki bağlantının anlaşılmasını amaçlamaktadır Su tutmayan yüzey üzerine bırakılan bir su damlası -pürüzlülüğün derecesine bağlı olarakyüzeyi tamamen ıslatmayabilir Bu durumda damla sadece belirli noktalardan yüzeye tutunur (Şekil 1), ve yüzey üzerindeki hareketi de bu tutunma noktaları arasındaki atlamalar şeklinde gerçekleşir [1] Bu çalışmalara katkı sağlaması umuduyla spektroskopi temelli yeni bir teknik geliştirmekteyiz [2] Bu teknikte su tutmayan yüzey üzerinde bulunan su damlası kızılötesi bir lazer kullanılarak ısıtılmakta, ve meydana gelen hacim değişiklikleri damla içinde oluşturulan fısıldayan galeri modları yardımıyla izlenmektedir Kullandığımız tekniği klasik temas açısı ölçümlerinden farklı kılan özellikler mikrometre boyutundaki damlalarla çalışabilmemiz ve oluşturduğumuz hacim değişikliğini bir yoğuşma hücresi yardımıyla- geri dönüşümlü olarak kontrol edebilmemizdir Aerojel, nanoparçacık, ve tanecik-nanoparçacık karışımı su tutmayan yüzeyler kullanarak yapmış olduğumuz ilk denemelerde kızılötesi lazerin gücünü bir sinüs dalgası şeklinde değiştirerek, fısıldayan galeri modlarının gözlendiği dalgaboyunun zamana bağlı değişimini izledik (Şekil 2-3) Modlardaki değişim aerojel yüzeylerde sinüs dalgası şeklinde olup lazer gücündeki değişimi yansıtırken, nanoparçacık yüzeylerde sinüs dalgasından sapmalar görüldü Tanecik-nanoparçacık karışımı yüzeylerde ise bu sapmalar daha da arttı Sinüs dalgasındaki bozulmalar ani hacim değişikliklerine karşılık gelmektedir ve su damlasının haraketi sırasında yüzeyle olan temas noktaları arasındaki atlamalara işaret etmektedirbu yönüyle, kullandığımız teknik su tutmaz yüzeylerde görülen farklı ıslatma türlerinin incelenmesinde yararlı olabilir Şekil 1 (üst) : Damlanın su tutmayan üzerindeki duruşunu gösteren temsili çizim Şekil 2-3 (sağ): Aerojel (üst), ve tanecik-nanoparçacık karışımı (alt) yüzeyler ile yapılan ölçümlerde fısıldayan galeri modlarının zamana bağlı değişimi

Single Wall Carbon anotubes Under Uniaxial Strain GDereli, Vardar* and ÖEyecioğlu** Deparment of Physics,Yildiz Technical University,Istanbul,Turkey, gdereli@yildizedutr *Deparment of Physics,Yildiz Technical University,Istanbul,Turkey, necativardar@gmailcom ** Deparment of Physics,Yildiz Technical University,Istanbul,Turkey, oeyeci@yildizedutr Single Wall Carbon Nanotubes (SWCNTs) have attracted wide attention for application in nano-devices due to their remarkable electronic and mechanical properties Depending on their chirality, they could be metal or semiconductor Electronic and mechanical properties of semiconducting single wall carbon nanotubes can also be modulated by an application of uniaxial strain In this study, we will report on the change of electronic and mechanical properties of semiconducting single wall carbon nanotubes under uniaxial strain Changes in the electronic structure will be displayed through Fermi energy level, density of states and energy band gaps of the semiconducting SWCNTs Change in the mechanical properties will be expressed in terms of elastic limit, Poisson ratio and Young s modulus of the SWCNTs During our simulations we used the parallel, Order N Tight-Binding Molecular Dynamics technique which is improved and successfully applied to SWCNTs simulations by G Dereli et al The research reported here was supported through the Yıldız Technical University Research Found Project No: 24-01-01-04 Simulations are performed in parallel environment at Carbon Nanotube Simulation Laboratory of Yıldız Technical University, Physics Department(http://wwwyildiz/edu/tr/~gdereli/lab_homepage/indexhtml)

Density Profiles and Inertia Moments of Interacting Bosons in Anisotropic Harmonic Confinement A I Mese 1, P Capuzzi 2, Z Akdeniz 3 and S E Okan 1 1 Department of Physics, Trakya University, 22030 Edirne, Turkey 2 Consejo acional de Investigaciones Cient ıficas y T ecnicas and Departamento de F ısica, FCEy, Universidad de Buenos Aires, Buenos Aires, RA-1428, Argentina 3 Physics Department, Piri Reis University, 34940 Tuzla, Istanbul, Turkey We study a rubidium gas of few atoms trapped by anisotropic two-dimensional harmonic potential, interacting via a K 0 (r) potentials [1] which is proper for two dimensional systems within the variational approximation Increasing the anisotropy of the confinement potential can drive the system from a two-dimensional 2D to a one-dimensional 1D configuration We found analytical expression for the inertia moment as a function of the number and position of the particles in the system Our results of the ground state configurations are compared with recent experiments [2] and published numerical results [3,4] and we obtained a satisfactory agreement [1] Nelson D R and Seung H S, Phys Rev B, 39 9153, 1989 [2] M Saint Jean and C Guthmann, J Phys: Condens Matter 14 (2002) 13653 13660 [3] A I Mese, P Capuzzi, J Phys: Condens Matter 20, 335222, 2008 [4] S W S Apolinario, B Partoens, and F M Peeters, Physical Review E 72, 046122 2005

Localization-Delocalization Transition in Ultracold Atomic Mixtures Patrizia Vignolo Institut on Linéaire de ice, C RS-France We propose an experiment to study the transport properties of a Bose-Einstein condensate in the presence of short-range correlated disorder where defects appear as dimers (random-dimer model) We suggest an experimental scheme and calculate the parameters entering the effective Hamiltonian for a realistic experiment where a first atomic species plays the role of impurities for the second one We show that a localization-delocalization transition occurs when the interspecies scattering length is increased, and evaluate the localization length and the transmittivity across this transition

Multilayered Quantum Wires and Quantum Dots Şaban Aktaş Department of Physics, Trakya University, Edirne 22030, Turkey sabana@trakyaedutr The binding energy of a hydrogenic impurity in the multilayered quantum wires and dots is investigated as a function of the barrier thickness for different impurity positions under the external electric and the magnetic fields Within the effective mass approximation, the ground state binding energy of a hydrogenic impurity is found employing a variational method It is found that the binding energy in critical barrier thickness shows an increase or decrease depending on the impurity position, the magnetic and the electric field strengths

The Binding Energy of the Multilayered Spherical Quantum Dot under a Magnetic Field F K Boz, S Aktas, S E Okan Department of Physics, Trakya University, Edirne 22030, Turkey figenb@trakyaedutr The binding energy of an impurity located at the center of multilayered spherical quantum dot (MSQD) is reported under the influence of a magnetic field Within the effective mass approximation, the binding energy has been calculated using the fourth order Runge- Kutta method without magnetic field A variational approach has been employed if a magnetic field is present The binding energy in MSQD with equal dot and barrier thickness is calculated Our results show that the structural confinement is very effective for thin MSQD, and the influence of magnetic field is more effective according to the geometric effect for thick MSQD

Density-of-State and Transport Properties for Random Dimer Hamiltonian SSucu 1, ŞAkatş 1, PVignolo 2, ZAkdeniz 3, SEOkan 1 1) Deparment of Physics, Trakya University, Edirne-22030, Turkey 2) Institut on Linéaire de ice, C RS-Fransa 3) Piri Reis Üniversitesi, Đstanbul-Tuzla, Turkey We study the transport prorerties and density-of-state of Bose-Einstein Condensation in periodic optical lattice with short-range correlated disorder One of the simplest and succesfull examples of correlate disorder is the short-range order of the Random Dimer Model(RDM) It consists in the random distribution of dimers along a tight-binding linear chain; this is realized when one of the two-site energies of the chain is assigned to couples of adjacent sites; thus one of the components of the lattice is a cluster made by a couple of sites with the sama energy (E2_E2) or different energy (E2_E1) We describe the system by means of a 1D Bose-Hubbard Hamiltonian, using a renormalization of the scattering lengths to embody the transverse confinement The Hamiltonian is not explicitly solved, but the whole lattice is reduced to a single dimer by a renormalization/decimation procedure Incoming and outgoing leads are connected to the effective dimer and the steady-state transport coefficient of the bosons is inferred from the evaluation of the scattered wave function of the leads due to the presence of the dimer

Effect of Laser on Quantum Well Bahadır Bekar, Şaban Aktaş, Figen Karaca Boz, Ş Erol Okan Department of Physics, Trakya University, 22030 Edirne, Turkey In this work, we are investigated effects of laser on symetric quantum square well using the finite different method The effects of the different amplitude laser on the binding energy are observedthe binding energy decrases with increasing amplitute of laser this behavior was presented in the Ref[1,2] References: 1) EC iculescu, LM Burileanu, A Radu Density of impurity states of shallow donors in a quantum well under intense laser field Superlattices and Microstructures 2008 2) E Kasapoğlu, H Sari, I Sökmen Binding energy of impurity states in an inverse parabolic quantum well under magnetic field Physica B 390 (2007) 216 219 3) H Sari, E Kasapoğlu, I Sökmen The effect of an intense laser field on magneto donors in semiconductors Physics Letters A 311 (2003) 60 66 4) F M S Lima, M A Amato,, L S F Olavo, O A C unes, A L A Fonseca,1 and E F da Silva, Jr Intense laser field effects on the binding energy of impurities in semiconductors 101103/PhysRevB75073201 5) Q Fanyao, LA Fonseca and, OAC unes Intense Laser Field Effect on Confined Hydrogenic Impurities in Quantum Semiconductors phys stat sol (b) 197,349 (1996) 6) C S Han Dressing Effect on the Electron-Atom Scattering in Intense Laser Field CHINESE JOURNAL OF PHYSICS VOL 31 NO 3 JUNE 1993 7) Yaşam Saften yüksek lisans tezi 2007 8) Emine Ozturk, ismail Sokmen Effect of the intense laser field on the valance band for Ga 1 x Al x As/GaAs heterostructure Superlattices and Microstructures Volume 45, Issue 1, January 2009, Pages 16-21

The Multilayered Cubic Quantum Dot Under the External Fields Ozge Kilicoglu, Saban Aktas, Figen Karaca Boz and SErol Okan Trakya University Art and Science Faculty Physics Department, Edirne, Turkey In this work, we have investigated the binding energy of the hydrogenic impurity of the multilayerd cubic GaAs(Ga,Al)As quantum dot (MCQD) as a function of the barrier thickness and the inner dot thickness under the electric and magnetic field strengths We calculate the ground state energy implementing the finite difference method The binding energy of hydrogenic impurity located at the center of a quantum dot has been studied with a variational approachwe found that the binding energy depends on the geometry of the dot, the magnetic and the electric field strengths Our results are good agreement with the pervious works

Water Dynamics in the Hydration Shell of a Protein Cem Servantie Faculty of Engineering and atural Sciences, Sabanci University, Istanbul, Turkey Water is essential for the stability and function of proteins For instance the equilibrium shape of a protein is dictated by the hydrophobic folding process Moreover, water modies dynamical properties of proteins such as the dynamic transition temperature, T d, above which proteins are biologically active The dynamics of the hydration shell water/protein association for two dierent folded proteins (lysozyme and myoglobin) are studied thanks to molecular dynamics simulations The results show that the number of water molecules within a cuto distance of each residue scales linearly with protein depth Keeping track of the water molecules within the cuto sphere, one can compute an effective residence time, scaling inversely with depth index at physiological temperatures and a temperature independent stretch exponent A depth independent orientational memory loss is obtained for the average dipole vector of the water molecules within the sphere when the protein is functional The hydration layer surrounding the protein is slaved by the fluctuations of the residues below the transition temperature At the transition, the slavery process ceases and water molecules collectively make the protein more exible, slowly relaxing matter

Reorientation of Carbon anotubes by Liquid Crystal Mediums S Eren San Department of Physics, Gebze Institute of Technology, 41400, Kocaeli, Türkiye erens@gyteedutr Carbon nanoparticle-liquid Crystal dispersions have been subject for scientific interest not only because they are efficient candidates for improving the performance of Liquid Crystal (LC) based devices but also such systems are promising for controlling the orientation of carbon nanotubes 1-2-3 In the scope of this work, Single Walled Walled Carbon Nanotubes (SWCNT) are employed in Nematic LC host so that an electrically and magnetically steered switch structures would be constructed Proposed devices exploit the conductivity anisotropy of nanotubes in combination with the reorientation of Nematic LC, which sweeps and reinforces the neighbour nanotubes The performances of the systems are characterized by conductivity measurements It was found that such systems could be proposed as sensors and nano-electronic components References: [1] I Dierking, G Scalia, P Morales, Advanced Materials, 16, 865 (2004) [2] MD Lynch, DL Patrick, ano Letters, 2, 1197 (2002) [3] I Dierking, S E San, Applied Physics Letters, 87 233507, (2005) 233507

Density Functional Theory Study on Molecular Structure and Vibrational Spectra of M-methylaniline M Kumru, T Bardakçı, L Sarı Fatih University, Faculty of Arts and Sciences, Department of Physics, 34500 Büyükçekmece, Istanbul, Turkey We have discussed the applicability limits of HF, MP2 and DFT-B3LYP methods on m- methylaniline in our previous work* We have found the DFT-B3LYP method very promising for vibrational spectral analyses In this study, we extend DFT calculations with different basis sets for more appropriateness to exprimental results The optimized molecular structures, vibrational frequencies and coresponding vibrational assigments of m- methylaniline have been obtained from the DFT-B3LYP, DFT-B3PW91 and DFT-PBEPBE methods implementing the 6-311G+** and aug-ccpvqz basis sets Scale factors, which bring computational frequencies in closer agreement with the experimental data, have been calculated for predominant vibrational motions of the normal modes at each level considered All observed harmonic IR and Raman bands of m- methylaniline have been assigned in the frameworks of the calculations The comparison of calculations with FT-IR and FT-Raman spectra of m- methylaniline have been carried out Keywords: m-methylaniline, Infrared and Raman spectra, Ab initio calculations, Density functional theory (DFT), ormal mode * A Altun, K Gölcük, M KUMRU, Journal of Molecular Structure (Theochem) 625 (2003) 17 24

Optical and Microstructural Properties of Tm 3+ Doped (1-x)TeO 2 -(x)zno 5TiO 2 Glasses Đdris Kabalcı Harran University, Education Faculty, Physics Education, Şanlıurfa kabalci@harranedutr, kabalci@ituedutr Tellurite based optical glasses exhibit significant properties which give them important industrial applications such as fiber lasers, fiber optic amplifiers, and laser hosts The aim of this investigation is the fabrication and characterization of the ternary tellurite based glasses with zinc oxide-titanium oxide by using melt-quenching techniques In this work, the optical and microstructural properties of Tm 3+ doped (1-x)TeO 2 -(x)zno-5tio 2 glasses were synthesized for different ZnO glass compositions From measurements of the optical absorption (UV-VIS) on very thin bulk glass samples, the optical band gap (E g ) was determined for the different compositions In addition, the density of each glasses was determined by using Archimede s prenciple with distilled water as the immersion liquid Furthermore, glass characteristic temperatures such as, glass transition (T g ), crytallization (T c ), and melting temperatures (T m ) were determined by using Differantial Thermal Analiysis (DTA) investigations in the temperature range between 20 and 700 o C with the heating rate of 10 o C/min Crytallization types of each glass samples were characterized by FT-IR spectroscopy and XRD techniques Keywords: Tellurite glasses, thermal analysis, energy band gap, laser materials

Simulation of Atomic and Molecular Clusters and Complexes Mustafa Böyükata Department of Physics, Bozok University, 66200 Yozgat, Turkey In this talk our resent studies on simulation of atomic and molecular clusters and complexes will be presented Structural and energetic analysis have been realized for pure metal clusters (Fe, Au, Ti, V, Cr, Cu and Pd) [1-5] via Molecular Dynamics (MD) by using pair potentials Characteristic changes in structural arrangements of atoms have been observed around energetically magic sizes Similarly, rearrangement approximation has been improved for Ar n CO 2 complexes [6] with MD method and pair-additive potentials Density Functional Theory (DFT) studies on hydrogenated boron clusters such as B 4 H n series and hydrogen hosting on cage B 5 -B 10 has been reported in Refs [7-9], respectively The effect of metal (like Al and Ti) putting in boron clusters for hydrogenations are under investigations Various structural isomers for Al-doped boron microclusters and their hydrogenated complexes have been optimized by using DFT/B3LYP functional and 6-311++G** basis set [10] Our findings (binding energies, HOMO-LUMO energies, fragmentation energies and second order energy differences of these clusters) will be discussed in detail through comparing with literature [11-13] Acknowledgment This work is partially supported by TUBITAK (Grand No 108T466) References [1] Böyükata, M, et al, J Alloys and Compounds, 403, 349, (2006) [2] Böyükata, M, Physica E, 33, 182, (2006) [3] Böyükata, M, J Theo Comp Chem, 6, 81, (2007) [4] Böyükata, M,Belchior, JC, J Brazilian Chem Soc, 19, 884, (2008) [5] Böyükata, M,Belchior, JC, Croatica Chemica Acta, 81, 289, (2008) [6] Böyükata, M, et al, Canadian J Chem, 85, 1, 47, (2007) [7] Böyükata, M,Özdoğan, C, Güvenç, ZB, J Mol Struc-Theochem, 805, 91, (2007) [8] Böyükata, M,Özdoğan, C, Güvenç, ZB, Physica Scripta, 77, 025602, (2008) [9] Böyükata, M,Özdoğan, C, Güvenç, ZB, Romanian J Inf Sci Tech, 11, 59, (2008) [10] Frisch M J et al, GAUSSIA 03, Revision D01, Gaussian Inc, Wallingford, CT, (2004) [11] Atış, M, Özdoğan, C, Güvenç, ZB, J Quantum Chem, 107, 3, 729, (2007) [12] Liu, X, et Al, Phys Rev A 75, 063201, (2007) [13] Feng, JX, and Luo, YH, J Phys Chem A, 111, 2420, (2007)

DFT Study of Titanium-doped Boron Clusters: TiB n (n=1-9) M Akar 1, M Böyükata 1, Z B Güvenç 2 1 Department of Physics, Bozok University, 66200 Yozgat, Turkey 2 Department of Elect and Comm Eng, Çankaya University, 06530 Ankara, Turkey In this preliminary work the geometry optimizations have been carried out for titanium doped boron microclusters by using DFT/B3LYP functional and 6-311++G** basis set [1] The lower-lying energy configurations of TiB n clusters up to n=9 are presented The obtained stable structures of TiB n clusters for n=1-3,9 and for n=4-8 prefer two-dimensional and threedimensional arrays, respectively Binding energies, HOMO-LUMO energies, fragmentation energies and second order energy differences of these clusters have been obtained The results are compared with pure B n clusters [2] and any boron-metal complexes [3-6] Acknowledgment This work is supported by TUBITAK (Grand No 108T466) References [1] Frisch M J et al, GAUSSIA 03, Revision D01, Gaussian Inc, Wallingford, CT, (2004) [2] Atış, M, Özdoğan, C, Güvenç, ZB, J Quantum Chem, 107, 3, 729, (2007) [3] Liu, X, Zhao, GF, Guo, LJ, Jing, Q, Luo, YH, Phys Rev A 75, 063201, (2007) [4] Feng, JX, and Luo, YH, J Phys Chem A, 111, 2420, (2007) [5] Yang, Z, and Xiong, SJ, J Chem Phys, 128, 184310, (2008) [6] Yao, JG, Wang, XW, and Wang, YX, Chem Phys, 351, 1, (2008)

Benzene Hosting on 4-, 5- and 6-atom Cage Boron Clusters Elmas 1, M Böyükata 1, Z B Güvenç 2 1 Department of Physics, Bozok University, 66200 Yozgat, Turkey 2 Department of Elect and Comm Eng, Çankaya University, 06530 Ankara, Turkey A theoretical study based on Density Functional Theory has been performed to investigate the electronic structure of benzene hosted cage boron microstructures by using B3LYP functional and 6-311g basis set [1] Total energies, binding energies, HOMO-LUMO energy gaps, frequencies, electronic state, structural parameters and point groups of structures have been calculated for B m (C 6 H 5 ) n, (m=4,5,6 and n m) complexes Within a similar way of previous works [2,3] boron clusters here are used as bridge between the molecules It is observed that the cage form of the boron clusters have structural stability Acknowledgment This work is supported by TUBITAK (Grand No 108T466) References [1] Frisch, M J et al, Gaussian 03, revision D01, Gaussian, Inc, Wallingford, CT, 2004 [2] Qiu, Y Q et al, Chinese Science Bulletin 52, 2326 (2007) [3] Peng, B et al, Chemical Physics 356, 171 (2009)