Studi struktur keadaan transisi dan energi aktivasi abstraksi hidrogen pada toluena dengan radikal nitrat menggunakan metode DFT dan MP2 / Muhamad Fathor Rosid
| Main Author: | Rosid, Muhamad Fathor |
|---|---|
| Format: | Thesis NonPeerReviewed |
| Terbitan: |
, 2017
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| Subjects: | |
| Online Access: |
http://repository.um.ac.id/23967/ |
Daftar Isi:
- ABSTRAKRosidM.F.2017.StudiStrukturKeadaanTransisidanEnergiAktivasiAbstraksiHidrogenpadaToluenadenganRadikalNitratMenggunakanMetodeDFTdanMP2.SkripsiJurusanKimiaFMIPAUniversitasNegeriMalang.Pembimbing(I)Dr.YahminS.Pd.M.Si.(II)Drs.IdaBagusSuryadharmaM.S.KataKunciToluenaRadikalNitratStrukturKeadaanTransisiEnergiAktivasiDFTMP2ToluenamerupakansalahsatuhidrokarbonaromatikyangmemilikiperanpentingdalampembentukanVOC(VolatileOrganicCompounds)danmemilikireaktivitastinggidalampembentukanSOA(SeconderOrganicAerosol)diatmosfer.DilapisanatmosfersalahsatuprosespenghilangtoluenaadalahreaksinyapadawujudgasdenganradikalNO3padamalamhari.Reaksitersebutmenyebabkanterbentuknyapolusidiudara.Berbagaiupayatelahdilakukanuntukmengurangidampaktersebut.Salahsatunyamenelitireaksi-reaksiyangterjadipadatoluenaterutamareaksioksidasipadatoluena.Padastudiinistrukturkeadaantransisidanenergiaktivasiabstraksihidrogenpadatoluenadenganradikalnitratditelitimenggunakanmetodekimiakomputasi.PenelitianinibertujuanuntukmengetahuistrukturkeadaantransisienergiaktivasidanjalurutamapadatemperaturkamarreaksiabstraksihidrogenpadatoluenadenganradikalNO3menggunakanmetodeDFT.Tahapankerjadalampenelitianteoritisiniterdirienamtahapyaitu(1)menggambarstrukturreaktandanproduk(2)optimasigeometridanperhitunganfrekuensivibrasireaktan(3)optimasigeometridanperhitunganfrekuensivibrasiproduk(4)pencarianstrukturkeadaantransisidanperhitunganfrekuensivibrasinya(5)perhitunganenergikeadaantransisi(6)perhitunganIntrinsicCoordinateReaction(IRC).PerhitunganoptimasigeometridanfrekuensidilakukandenganmenggunakanmetodeDFTB3LYP.PerhitunganenergikeadaantransisidilakukandenganmetodeMP2(Second-OrderMoller-PlessetPerturbationTheory).Himpunanbasisyangdigunakanuntukperhitunganoptimasifrekuensivibrasidanenergiadalah6-311G(dp).Hasilpenelitianmenunjukkanbahwareaksiabstraksihidrogenpadatoluenadenganradikalnitratmenghasilkanenammacamstrukturkeadaantransisiyakni(1)abtraksihidrogenpadarantaisamping(TS-SEa0509Kkal/mol)(2)abstraksihidrogencincinposisiorto(TS-OaEa12302Kkal/mol)(3)abstraksihidrogencincinposisiorto(TS-ObEa12017Kkal/mol)(4)abstraksihidrogencincinposisimeta(TS-MaEa12278Kkal/mol)(5)abstraksihidrogencincinposisimeta(TS-MbEa12363Kkal/mol)(6)abstraksihidrogencincinposisipara(TS-PEa12746Kkal/mol).KeadaantransisiTS-Smerupakanyangpalingstabilsehinggajalurutamareaksiabstraksihidrogentoluenadenganradikalnitratadalahradikalbenzil.ABSTRACTRosidM.F.2017.StudyofTransitionStateStructureandActivationEnergyHydrogenAbstractionToluenewithNitrateRadicalusingDFTandMP2Method.UndergraduateDepartmentofChemistryMathematicsandScienceFaculty.StateUniversityofMalang.Lecturer(I)Dr.YahminS.Pd.M.Si.(II)Drs.IdaBagusSuryadharmaM.S.KeywordTolueneNitrateRadicalTransitionStateStructureActivationEnergyDFTMP2TolueneisoneofaromatichydrocarbonthathasimportantroleinformationofVOC(VolatileOrganicCompounds)andhashighreactivityinformationofSOA(SeconderOrganicAerosol)inatmosphere.IntheatmosphereoneprocessofToluenesremoverisitsreactionongasstatewithNO3radicalinthenight.Thatkindofreactionthencreatepollutionintheair.Earlierstudieshastriedtodecreaseimpactofthereactiononeofthemisbyresearchtoluenesreactionparticularlytheoxidation.Inthiscasetransitionstatestructureandactivationenergyofhydrogenabstractionintoluenewithnitrateradicalwasobservedusingcomputationchemistrymethod.ThisresearchwasaimedtoknowthetransitionstatestructureactivationenergyandprimaryproductintheroomreactionofhydrogenabstractionintoluenewithradicalNO3usingDFTmethod.Thereweresixstepinthisresearch(1)drawthestructureofreactantsandproduct(2)optimizationofgeometryandcalculationofitsreactantsvibrationfrequency(3)optimizationofgeometryandcalculationofproductvibrationfrequency(4)researchthetransitionstatestructureandcalculationofitsvibrationfrequency(5)energycalculationoftransitionstateand(6)calculationofIntrinsicCoordinateReaction(IRC).TheenergycalculationoftransitionstatewasdonewithMP2(Second-OrderMoller-PlessetPerturbationTheory)method.Thebasesetusedforoptimizationcalculationvibrationfrequencyandenergyis6-311G(dp).Theresultshowsthathydrogenabstractionreactionintoluenewithnitrateradicalwasthenproducesixkindoftransitionstatestructure(1)hydrogenabstractionofsidechain(TS-SEa0509Kcal/mol)(2)hydrogenabstractionoforthopositionringTS-OaEa12302Kcal/mol)(3)hydrogenabstractionoforthopositionring(TS-ObEa12017Kcal/mol(4)hydrogenabstractionofmetapositionring(TS-MbEa12363Kcal/mol)(5)hydrogenabstractionofmetapositionring(TS-MbEa12363Kcal/mol)and(6)hydrogenabstractionofparapositionring(TS-PEa12746Kcal/mol).TransitionstateofTS-Sisthemoststableonesothatthemainlineofhydrogenabstractionreactionintoluenewithnitrateradicalisbenzylradical.