A Study of The Geometrical Optimization and ‎Energies of Carbon Nanoribbons: B3LYP/DFT

يشتمل البحث الحالي على الامثلية الهندسية والطاقات ثلاث تراكيب من شرائط الكاربون النانوية باستخدام الهجينة ذات المعاملات الثلاث من طريقة دالية الكثافة. تم تطبيق الدوال الاساس 6-31G لدراسة تأثير طول الشرائط على الطاقات والخواص الالكترونية للتراكيب. بينت النتائج ان الدالة الهجينة المستعملة كانت مناسبة لحسابات المعاملات الهندسية للتراكيب. كما ان فجوة الطاقة قد ازدادت بزيادة طول الشريط نتيجة لتغير طاقات كل من المستوي الجزيئي العلوي المشغول والمستوي الجزيئي السفلي الفارغ لشرائط الكاربون النانوية. الشريط الاقصر طولاً يمتلك اعلى مرونة الكترونية وفعالية اكبر من الشريط الاطولThis study deals with the geometrical optimization and energies of three structures of carbon nanoribbon using the B3LYP-DFT hybrid functional. 6-31G basis sets was employed to study the effect of the ribbons length on the energies and electronic properties of the structures. The results showed that the hybrid functional used is suitable for calculations the geometrical parameters of the structures. So, the energy gap was increased with increasing the length of the ribbon due to the change  of both the HOMO and LUMO energies of the carbon nanoribbons. The shortest the ribbon the higher electronic softness and the more reactive it is as compared to the long ribbo

Electronic Transitions and Photovoltaic Properties of New Compounds as Organic Dye Sensitizers for Solar Cell

This work deals with electronic and photovoltaic properties of new compounds as organic dye sensitized for solar cell. The ground state calculations are carried out by employing the B3LYP-DFT method and the TD-DFT for excitation properties at the Gaussian 09 package of programs. The results showed the HOMO and LUMO are slightly different and this suggests that different structures play significant roles on electronic properties and improving the electron accepting ability. The obtained values of energy gap and the open circuit voltage are the parameters manipulating to improving the quality of solar cell devices. Also, the results show these compounds can be used as organic sensitizers for solar cell due to possibility of the electron injection process from the compounds to the conduction band of TiO2

Investigation of the Effect of Poly-Methyl Subgroups on the Electronic and Spectroscopic Properties of Fullerene C60 Molecule

This study focuses on employing the B3LYP hybrid functional method with 6-31G basis sets to study the effects of the addition of poly-methyl subgroups on the electronic and spectroscopic properties of fullerene C60 cage molecule. Koopman,s method was used to calculate some important electronic variables, such as, the ionization energy, electron affinity and electronegativity. We showed that the location and the subgroups number of methyl in fullerene molecule effect on the calculated  energies. The addition of the methyl reduces the energy gap, means we construct new molecular electronic structures which can be used in many applications. Keywords: B3LYP, Koopmans theorem, Energy Gap and Polarizability

Technological scheme of the combined geothermal-hydrocarbon system for the production and storage of energy resources

The complex researches of schemes of extraction and storage of hydrocarbons and geothermal energy are executed in the work. In particular, according to the location, logistics and nature of the processes of generation, transportation, evacuation, injection and local utilization of hydrocarbon and geothermal energy sources, the scheme is divided into subspecies of consumer regional order of electricity, hydrocarbon and chemical energy and hydrogen. It is shown that the tasks of extraction of natural or synthesized hydrocarbons, geothermal energy and subsequent transformation into the required form of commodity resource can be unified with the organization of circuit-combined technologies. At the same time, the developed technological scheme implements the concept of storage of the required amount of energy resources on the one hand and regulation of production capacity for consumption – on the other. The reduction of current energy costs for the implementation and operation of systems with updated functional systems for a total of 20–45%. It is proved that the selection of the scheme of unified extraction and storage energy systems in accordance with the projected order of energy and energy resources, due to the capabilities of productive reservoirs, leads to minimization of capital costs for their construction on a modular basis. Research of application of combined technologies of dual extraction-storage of heat carriers-hydrocarbons is a perspective direction of researches