III International Conference

PP-III-74MODELLING OF TEMPERATURE DEPENDENCES OF YIELDS OF PRODUCTSOF CATALYTIC PROCESSES WITH PARTICIPATION OF HYDROCARBONSLapidus A.L., Smolenskii E.A., Ryzhov A.N, Bavykin V.M., Myshenkova T.N.N.D. Zelinsky Institute of Organic chemistry, RAS, Moscow, RussiaE-mail: smolensk@cacr.ioc.ac.ruIn [1] based on the concept «the molecular topological form (МТF)», suggested in [2],has been proposed the term «the skeletal molecular form (SМF)» - set of 3n space coordinatesF = { xi , yi, zi} (i=1, …, n) (1)for conformers of compounds with n atoms different from H, including hydrocarbons whichwill be considered further. As well as in the case of МТF, the set (1) is broken into threeclasses: (1) atoms at tops of the convex figure, applicable to SМF - "external"; (2) atoms onsides of this figure - "boundary" and (3) “internal atoms” of SМF.The geometrical figure formed by external atoms in [1] is named visualization of SМF.By analogy to atoms, we shall name external those C-C bounds which are edges ofvisualization SМF. The working hypothesis is put forward: it is necessary, that given atom ofcarbon or C-C bounds have to be external for participation of this atom of carbon or C-Cbound in catalytic process on an even surface of the catalyst.The measure of availability of i-th atom (“external”) in j-th conformer (with nonplanarSМF) is determined as p ij =1-(Ω ij /2π) (Ω ij – a solid angle in top of visualization of SМF,applicable to this atom), and C-C bounds (“external”) between i-th and k-th atoms in thisconformer (bounds (i, k)) - as p ik,j =1-(α ik,j /π) (α ik,j – two-sided angle at a applicable edge ofvisualization). If SМF is flat, than p ij =1-(α ij /π) (α ij – angle at applicable top of visualization),than availability of all bounds are equal 1. In the case of linear SМF all of bounds are equaland trailer atoms. Availability of atoms and bounds, not being external, are considered to beequal 0.Then in n-ALKANE, in view of equivalence of i-th and n-i+1-th atoms and bounds (i,i+1) and (n-i, n-i+1), the probability of attack of atom C (C-C bounds) is calculated underformulaspi⎛NN= fi⎜∑j ij ∑⎝ j= 1j=1( n) ⎜ ω p + ω p( ) njn−i+1 j⎟ ⎞⎠, (2)608