International Journal of Innovative Research in Science, Engineering and Technology. (An ISO 3297: 2007 Certified Organization)

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1 ISSN(Onlin) : ISSN (Print) : 7-71 (An ISO 97: 7 Crtifid Orgniztion) Vol., Issu 1, Octobr 15 Diffrntil Scttring Cross Sction Clculti ons for Low Enrgy Elctron Intrction with Polytomic Mthyl chlorid (CH Cl) nd Mthyl fluorid (CH F) Molculs Jyntill G. Riyni 1 Associt Profssor, Dprtmnt of Physics, Shri M. M. Scinc Collg, Morbi, Gujrt, Indi 1 ABSTRACT: In this ppr, w rport th diffrntil scttring cross sction for low nrgy lctron intrction with polytomic Mthyl chlorid (CH Cl) nd Mthyl fluorid (CH F) molculs. Th rottionl xcittion lctron impct diffrntil cross sctions (DCS) for polytomic Mthyl chlorid (CH Cl) nd Mthyl fluorid (CH F) molculs r clcultd, t low nrgy 5. V nd 7. V rspctivly. Th Born Eikonl Sris Approximtion mthod nd th hrd sphr dipol intrction potntil modl r mployd in th prsnt invstigtion. Th prsnt DCS rsults obtind in ngulr rng ( to18 ). r comprd with xprimntl nd othr thorticlly clcultd rsults. Th prsnt rsults r found b to b quit rmrkbl grmnt with thos of comprd rsults. KEYWORDS: Dipol potntil, Diffrntil cross sction, Born Eikonl Sris Mthod. I. INTRODUCTION Mthyl chlorid is usd minly in th production of silicons. CH Cl is lso usd in th production of griculturl chmicls, mthyl cllulos, qutrnry mins, butyl rubbr nd strting mtril in th mnufctur of such chmicls s mthyl mrcptn, mthyln chlorid, chloroform, crbon ttrfluorid. Du to concrns bout its ozon-dplting potntil, it is no longr prsnt in rfrigrtors. Low lvls of mthyl chlorid occur nturlly in th nvironmnt. Highr lvls my occur t chmicl plnts whr it is md or usd. Acut (short-trm) xposur to high concntrtions of mthyl chlorid in humns hs cusd svr nurologicl ffcts. Mthyl chlorid hs lso cusd ffcts on th hrt rt, blood prssur, livr, nd dnys in humns. Chronic (long-trm) niml studis hv shown livr, dny, spln, nd cntrl nrvous systm (CNS) ffcts. Inhltion studis hv dmonstrtd tht mthyl chlorid cuss rproductiv ffcts in ml rts, with ffcts such s tsticulr lsions nd dcrsd sprm production. Humn cncr dt r limitd. It hs clssifid mthyl chlorid s Group D crcinogn. In smiconductor mnufcturing, mthyl fluorid (CH F) is usd in plsm tching of silicon compound films. Mthyl fluorid CH F nd mthyl chlorid CH Cl molculs ply potntil rol in th dpltion of th Erth s protctiv ozon lyr nd ll r ctiv grnhous gss. In ddition thy r lso importnt in th chmicl industry, for xmpl, in smiconductor tching, s rfrigrnts, nd s mthylting gnts. Th low nrgy lctron-molcul collisions r not only of fundmntl intrst but of immns importnc for mny pplictions. For xmpl, dtild knowldg of ths procsss is rquird for Th Clcultions of cross-sctions nd othr prmtrs for lctron collisions with polytomic molculs r considrbly mor difficult thn th nlogous studis with tomic trgts. This is du both to th loss of symmtry in molculr systms nd th much grtr difficulty in rprsnting th trgt wv function. In ddition molculs hv vibrtionl nd rottionl dgrs of frdom which cn b xcitd by lctron impcts. It is thrfor not surprising tht clcultions of lctron polytomic-molcul impcts r oftn much crudr thn thir lctron tom countrprts. Howvr, mny of th succsss chivd in lctron molcul scttring hv usd ids originlly dvlopd for toms. A comprhnsiv survy of computtionl mthods for lctron molcul collisions cn b foundd in Rf.[1,]. Copyright to IJIRSET DOI:1.158/IJIRSET

2 ISSN(Onlin) : ISSN (Print) : 7-71 (An ISO 97: 7 Crtifid Orgniztion) Vol., Issu 1, Octobr 15 Th min gol in this work is to provid bsolut vlus rottionl xcittion diffrntil cross sction (DCS) for lctron- intrction with polytomic for polytomic mthyl chlorid (CH Cl) nd mthyl fluorid (CH F) molculs t low nrgy 5 V. nd 7. V. in ngulr rng ( to18). Th Born Eikonl Sris (BES) Approximtion mthod nd hrd sphr dipol intrction potntil modl is mployd for prsnt clcultions. Th hrd sphr cut-off prmtr is considrd s D/, whr D is dipol momnt of molcul.[,7] Th prsnt DCS rsults r comprd with th rsults of Vrll M.T. t-l [8,9] clcultd using th Schwingr multichnnl mthod with norm-consrving psudo potntils.nd vilbl xprimnt dt. It is found tht th prsnt rsults r in good grmnt with thos of comprd rsults. II. METHODOLOGY In ordr to tk into ccount somwht highr trms of Born sris, on cn us Eikonl pproximtion. Ashihr t-l [5] mployd Glubr formultion in Eikonl pproximtion for lctron dipol collisions. Thy clcultd cross sction for strongly polr molculs. Although this pproximtion is originlly high nrgy pproximtion, it hs bn pplid succssfully to th low nrgy lctron tom collision (Grjuoy t-l []). In th prsnt invstigtions n ttmpt is md to mploy Born Eikonl Sris (BES) mthod for th cross sctionl clcultions for th low nrgy lctron polytomic molcul collision []. Th intrction potntil V(r) cn b xprssd in following form, n r V ( r) q P (ˆ, r n1 n nodd r --- (1) P ( rˆ, Whr r > nd r < r th lrgr nd th smllr of r nd n is th Lgndr polynomil of th ordr-n. is th prmtr which indicts finitnss of th dipol nd rltd to th dipol momnt by th rltion D = q. Tng n = 1 only on cn gt th xprssion for lctron finit dipol intrction potntil nd it is mployd in cylindricl polr co-ordint, on cn nm linr dipol modl. In th prsnt invstigtion following form of th intrction dipol potntil is mployd [5,,7]. V( r, V( b, z) for z < --- () D V( r, V( b, z) P1 ( r, b z for z > --- () Whr, - is th hrd sphr prmtr (cut-off prmtr). Th formul for th Eikonl phs shift function χ(b) is givn by, D. ( b) ( b zdz z ) / γ - is th dirction cosin of th dipol xis with rspct to th polr xis. A sris xpnsion of scttring mplitud s givn by, D f E 1 xp( ) f E f id k ( ) E D --- () ---- (5) ---- () ---- (7) Whr K (Δ) - is Bssl function, Δ= -kf is momntum trnsfrrd. Th diffrntil cross sction (DCS) for thr trms in Born Eikonl Sris Approximtion cn b xprssd s follow, Copyright to IJIRSET DOI:1.158/IJIRSET

3 ISSN(Onlin) : ISSN (Print) : 7-71 (An ISO 97: 7 Crtifid Orgniztion) Vol., Issu 1, Octobr 15 d d kf ( j m j jm ; ) j f E1 f E f E --- (8) Summing ovr m j nd vrging ovr m jo on gts th DCS for th rottionl trnsition j j o +1. Diffrntil Scttring cross-sction (DCS):- Whr d d A md/ h kf 1 A 9 1 A A j 1 ( j 1 ) ( j )( j 1) j * 175 ( j 5)( j 1)( j ( j 1) 5( j 1) 1) III. RESULTS AND DISCUSSION 5 ( j ( j 1) 1) ---- (9) Th min intrst of th prsnt work is to discuss rottionl xcittion diffrntil scttring cross-sction (DCS) for lctron collision with polytomic mthyl chlorid (CH Cl) nd mthyl fluorid (CH F) molculs t nrgy 5. V. nd 7. V rspctivly. Th rottionl xcittion diffrntil cross-sctions r clcultd using Born Eikonl Sris (BES) pproximtion mthod nd mployd hrd sphr dipol intrction potntil modl. Th hrd sphr prmtr is tkn s = D/, whr D-is dipol momnt of rspctiv molculs. Th prsnt rsults r comprd with thorticl rsults of Vrrl M.T. t-l [8,9] clcultd using th Schwingr multichnnl mthod with normconsrving psudo potntils. Figur-1 shows th ngulr distribution curv of prsnt DCS rsults, clcultd for lctron scttring by polytomic mthyl chlorid (CH Cl) molcul t nrgy 5. V, using BES mthod nd considring hrd sphr dipol intrction potntil modl. Th hrd sphr prmtr is considrd s = D/, whr D-is dipol momnt of concrnd molcul. Th prsnt rsults r comprd with thorticl rsults of Vrrl M.T. t-l [8,9] clcultd using th Schwingr multichnnl mthod with norm-consrving psudo potntils.. As shown in th figur-1, th prsnt DCS rsults r found shrply dcrss t scttring ngl from 1 to 7 nd bov from 7 to 11 th prsnt DCS r dcrss smoothly, Thn, ths bcom minimum round th scttring ngl θ = 9 ftrwrd thy r incrss slowly up to scttring ngl 18. Th prsnt rsults r found slightly lowr thn s compr with th rsults of Vrrl M.T. t-l [8,9] in th ngulr rng btwn 5 to 11, th prsnt rsults bcom minimum t ngl 9 nd thy r found comprbl grmnt with th rsults of Vrrl M.T. t-l [8,9] in ngl btwn 1 to 1, but t highr scttring ngl from 1 to 18, th prsnt rsults r slightly highr thn thos of Vrrl M.T. t-l [8,9]. Th prsnt DCS rsults using BES mthod for hrd sphr dipol potntil r ovrll in good grmnt in with rsults of Vrrl M.T. t-l [8,9]. Copyright to IJIRSET DOI:1.158/IJIRSET

4 DCS ( 1-1 cm ) DCS ( 1-1 cm ) DCS ( 1-1 cm ) DCS ( 1-1 cm ) ISSN(Onlin) : ISSN (Print) : 7-71 (An ISO 97: 7 Crtifid Orgniztion) Vol., Issu 1, Octobr CH Cl (Mhtyl Chlorid) DCS -CH Cl collision E=5. V. 1 1 CH Cl (Mthyl chlorid) DCS for -CH Cl collision E=7. V Figur.-1 Diffrntil cross sction (DCS) for -CH Cl t nrgy 5. V Figur.- Diffrntil cross sction (DCS) for -CH Cl t nrgy 7. V Figur- shows th ngulr distribution curv of DCS rsults, clcultd for lctron scttring by polytomic mthyl chlorid (CH Cl) molcul t nrgy 7. V, using prsnt mthod. Th prsnt rsults r comprd with thorticl rsults of Vrrl M.T. t-l [8,9]. As shown in th figur-, prsnt DCS rsults r found shrply dcrss t scttring ngl from 1 to 5 nd bov from 5 to 11 th prsnt DCS r dcrss smoothly, Thn, thy bcom minimum t scttring ngl θ = 9 ftrwrd thy r incrss slowly up to scttring ngl 18. Th prsnt rsults r found slightly lowr thn s compr with th rsults of Vrrl M.T. t-l [8,9] in th ngulr rng btwn 5 to 1, th prsnt rsults r found quit comprbl grmnt with th rsults of Vrrl M.T. t-l [8,9] in ngulr rng btwn 1 to 1, but t highr scttring ngl from 1 to 18, th prsnt rsults r slightly highr thn thos of Vrrl M.T. t-l [8,9]. In gnrl, th prsnt DCS rsults r found in good grmnt in with Vrrl M.T. t-l [8,9]. 7 CH F (Mthyl fluorid) DCS for -CH F collision E=5. V. 7 CH F (Mthyl fluorid) DCS for -CH F collision E=7. V Figur.- Diffrntil cross sction (DCS) for -CH F t nrgy 5. V Figur.- Diffrntil cross sction (DCS) for -CH F t nrgy 7. V Figur- shows th ngulr distribution curv of DCS rsults, clcultd for lctron scttring by polytomic mthyl fluorid (CH F) molcul t nrgy 5. V, using BES mthod. Th prsnt rsults r comprd with Copyright to IJIRSET DOI:1.158/IJIRSET

5 ISSN(Onlin) : ISSN (Print) : 7-71 (An ISO 97: 7 Crtifid Orgniztion) Vol., Issu 1, Octobr 15 thorticl rsults of Vrrl M. T. t-l [8,9]. Th prsnt rsults r found to b dcrsing t scttring ngl from 5 to 9 thn, thy bcom minimum t scttring ngl θ = 95 ftrwrd thy incrs slowly up to scttring ngl 18. Th prsnt rsults r found comprbl grmnt with thos of Vrrl M.T. t-l [8,9] rsults t th ngl btwn 5. to 1.. Th prsnt DCS rsults r in comprbl grmnt with th rsults of Vrrl M.T. t-l [8,9]. In gnrl, qulittiv grmnt is obsrvd btwn th prsnt nd thos of comprd rsults. Figur- shows th ngulr distribution curv of DCS rsults, clcultd for lctron scttring by polytomic mthyl fluorid (CH F) molcul t nrgy 7. V, using prsnt mthod.. Th prsnt rsults r comprd with thorticlly clcultd rsults of Vrrl M.T. t-l [8,9]. Th prsnt DCS rsults r found shrply dcrss t scttring ngl from 1 to nd bov from to 11 th prsnt DCS r dcrss smoothly, Thn, thy bcom minimum t scttring ngl θ = 8 ftrwrd thy r rpidly incrss up to scttring ngl 18. Th prsnt DCS rsults r found with good grmnt with thos of Vrrl M.T. t-l [8,9] rsults IV. CONCLUSION Th prsnt work rports on th clcultions of diffrntil cross sction (DCS) in ngulr rng ( to18) for lctron impct, rottionl trnsitions ( 1) for polytomic mthyl chlorid (CH Cl) nd Mthyl fluorid (CH F) molculs t low nrgy 5. V nd 7. V rspctivly. W hv mployd th Born Eikonl Sris (BES) pproximtion mthod nd th hrd sphr dipol intrction potntil modl for prsnt lctron-molcul collision. Th lctron collisions with thos molculs ply n importnt rol, for mny pplictions in plsm physics, tmosphric nd intrstllr modls, stllr tmosphrs, rdition physics, biophysics nd chmistry. Ths DCS dt cn b hlpful to provid undrstnding nd bhviour of mthyl chlorid (CH Cl) nd Mthyl fluorid (CH F) molculs. This mthod is wll stblishd for obtining cross sction with rsonbl ccurcy. Th prsnt rsults my b improvd by tng highr trm of BES mthod. Using th prsnt thory nd ssumption, on could find stbility of concrn polytomic molculs from its DCS dt. Thrfor w hv confidnc tht th mthodology my b usd to improv th molculr dt bs. Such dt st is ndd in vrity of pplictions in tomic & molculr physics nd chmistry. W r quit sur tht prsnt work will b inspiring rsrchrs in thos filds. REFERENCES [1] Ginturco F,A., J.Phys.B, Vol., 87,1991 [] Tnnyson J. B., Morgn L. A., R. Soc. A:, 57, 111, [] Christophorou L. G., Olthoff J. K., t-l, J. Phys. Chm. Vol.-, 1, [] Grjuoy E., Stin S., Phy. Rv., 97, 171, 1955 [5] Ashihr, I. Shimmur,K. Tkyngi J. Phys. Soc., Vol.-8, 17, [] Dsi H. S., Chhy V. M., Ind. J. Pur & Appl. Phys, Vol.-17,18, [7] Jin A., Thomposon D. G., J.Phys. B Vol.-1, 17, 198. [8] Vrll M.T., Brz. J. Phys. Vol-.,,. [9] Vrll M.T., Bttg H. F., Alxndr P., Brz. J. Phys. Vol. -, 1, 1. Copyright to IJIRSET DOI:1.158/IJIRSET