Estimating the Heats of Formation of Hydrocarbon Radicals by a Semiempirical Calculation

نویسندگان

  • Xiaoliang Ma
  • Harold H. Schobert
چکیده

Hydrocarhon free radicals play a very important role in many thermalchemistry processes. including combustion. petroleum and coal coking, coal liquefaction and pyrolysis. oil shale retorting, thermal stability of fuels as well as free rddiciij polymerization. To obtain heats of formation (AH",) of the radicals is very essential for the fundamental understanding of thermal chemistry and mechanism of the free radical process. Many experimcntal methods have k e n developed to determine AH", of free radicals. including halogenation kinetics, polyani relation. chemical activation, equilibrium study, electron-impact measurement, radical buffer, appearance energy, photoacoustic calorimetry, electrochemistry etc.11-31. However. the experimental determination of AH", of free radicals is complicated. difficult and expensive due to the instability

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

PDDG/PM3 and PDDG/MNDO: Improved semiempirical methods

Two new semiempirical methods employing a Pairwise Distance Directed Gaussian modification have been developed: PDDG/PM3 and PDDG/MNDO; they are easily implemented in existing software, and yield heats of formation for compounds containing C, H, N, and O atoms with significantly improved accuracy over the standard NDDO schemes, PM5, PM3, AM1, and MNDO. The PDDG/PM3 results for heats of formatio...

متن کامل

Heats of formation of platonic hydrocarbon cages by means of high-level thermochemical procedures

Hydrocarbon cages are key reference materials for the validation and parameterization of computationally cost-effective procedures such as density functional theory (DFT), semiempirical molecular orbital theory, and molecular mechanics. We obtain accurate total atomization energies (TAEs) and heats of formation (Δf H°298) for platonic and prismatic hydrocarbon cages by means of the Wn-F12 expli...

متن کامل

Determination of geomechanical parameters of Sarvak formation using seismic, and well-log data in one of the hydrocarbon fields at the southwest of Iran

Nowadays geomechanics plays a major role in optimizing the production and development stages of hydrocarbon reservoirs. The high cost of drilling wells and maintaining a functional well entails companies to utilize geomechanical modeling to determine the most efficient drilling path and the safest mud windows in order to maintain the stability of the well and prevent critical fracturing and col...

متن کامل

Investigation of the production of free radicals in ultraviolet irradiation using SnO2:Eu nanoparticles

In studying the ultraviolet (UV) radiation, one of the important factors is the possibility of generating a variety of free radicals inside the body by these radiations. In this paper, a method of estimating the amount of hydroxyl radicals produced by ultraviolet rays was investigated using nanoparticles of tin oxide doped with uropium. In this method, the change in absorption intensity of meth...

متن کامل

Transannular Interaction in N-Aryl-5-Azocanones, A Semiempirical Quantum Mechanics and UV Spectroscopy Studies

The ability of the present semiempirical quantum mechanics methods are surveyed for reproducing the transannular interaction in the bifunctional N-phenyl-5-azocanones. The AM1 method is the best with the order of reliability being Am1, PM3, MNDO and MINDO/3. AM1 calculations were then carried out for quantification of transannular interaction. The n(o) ionization potential has be...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2006