F

Facilitatedtransfer(atITIES)265●FFFacilitatedtransfer(atITIES)—Facilitatedtransferofanionacrosstheinterfacebetweentwoimmiscibleelec-trolytesolutions(ITIES)isanimportantclassofchargetransferreactionsatITIESinvolvingnotonlythetrans-ferringion,butalsoanotherionoraneutralligandwhichcanbedistributedoneithersideoftheinter-face[i].Thecouplingoftheiontransferatliquid–liquidinterfaceswiththehomogeneousionassociationorcomplexationshiftsthepartitionofthetransferredioninfavorofoneoftheadjacentliquidphases.Fig-ureshowstheschemeofvariouspathwaysforthetrans-ferofanionMz+inthepresenceofaneutralligandL.Thesepathwayscanbeclassifiedasthetransferbyinter-facialcomplexation(TIC),iontransferfollowedbyor-ganicphasecomplexation(TOC),oraqueouscomplex-ationfollowedbytransferofthecomplex(ACT)[ii].Theclassicaldescriptionofthemechanismasareactionwithoneelectrochemical(E)andonechemical(C)step,i.e.,E,EC,andCEreaction,respectively,assumedthatthepartitionoftheligandLisshiftedwhollyinfavoroftheorganicphase[iii].Thesereactionshavebeenstudiedmainlybycyclicvoltammetry[iv](Fig.),ACvoltam-metry[iii],andbycurrentscanpolarography[v].Fol-lowingthefirstattempttoexplainthevoltammetricbe-haviorintermsofthestandardiontransferpotentialandthecomplexstabilityconstant[i],afundamentalap-proachtothetransportprobleminpolarography[vi]andcyclicvoltammetry[vii,viii]hasbeendeveloped.Althoughalargenumberofiontransferprocessesofthistypewerestudied,kineticdataarefewpointingtoFacilitatedtransfer(atITIES)—Figure.VariousreactionpathwaysforthetransferofanionMz+inthepresenceofaneutralligandL,withhighlightedtransferbyinterfacialcomplexation(TIC).Reprintedwithpermissionfrom[ii].©ElsevierB.V.Facilitatedtransfer(atITIES)—Figure.Cyclicvoltammo-grams(.Vs−)ofsupportingelectrolytes(,)andmM-phenylethylammoniumion(,)intheabsence(A)andpresence(B)ofmM,,,-dibenzo-,,,,,-hexaoxacyclooctadecane(dibenzo--crown-)intheorganicphase.Reprintedwithpermis-sionfrom[iv].©ElsevierB.V.fastiontransferkineticswiththeapparentstandardrateconstant(reactionrate)exceedingcms−[ix,x].Anothertypeofthefacilitatedtransferisthatinvolv-ingmoleculeswithacid–baseproperties.Aconstructionofionpartitiondiagramofthesolute,whichisanalo-goustoPourbaix’spotential-pHdiagramswidelyusedinelectrochemistryofcorrosion,hasbeenproposedasaconvenienttoolthatmakesitpossibletorelatethevoltammetricbehaviortothepartitionoftheneutralandtheionicspecies,aswellastoacid–baseequilibriaintheadjacentliquidphases[xi].Refs.:[i]HomolkaD,HungLQ,HofmanováA,KhalilMW,KorytaJ,MarečekV,SamecZ,SenSK,VanýsekP,WeberJ,BřezinaM()AnalChem:;[ii]ReymondF,FermínD,LeeHJ,GiraultHH()ElectrochimActa:;[iii]KakutaniT,NishiwakiY,Os-akaiT,SendaM()BullChemSocJpn:;[iv]DvořákO,MarečekV,SamecZ()JElectroanalChem:;[v]YoshidaZ,FreiserH()JElectroanalChem:;[vi]MatsudaH,YamadaY,KanamoriK,KudoY,TakedaY()BullChemSocJpn:;[vii]KakiuchiT,SendaM()JElectroanalChem:;[viii]Rey-mondF,CarruptPA,GiraultHH()JElectroanalChem:;[ix]BeattiePD,DelayA,GiraultHH()ElectrochimActa:;[x]CaiCX,TongY,MirkinMV()JPhysChemSoc:;[xi]ReymondF,SteyaertG,CarruptPA,TestaB,GiraultHH()JAmChemSoc:ZSam266Falkenhagen,Hans●FFalkenhagen,Hans(May,,Wernigerode,Germany–June,,Rostock,Germany)Studiedphysics,mathematics,andchemistryinHeidelberg,Munich,andGöttingen.Ph.D.Göttingen,habilitationCologne./workingwithDebyeinZurichandLeipzig.Follow-ingappointmentsinCologneandDresden,from–ProfessorofTheoreticalPhysicsinRostock.To-getherwithDebyehecouldexplainthedispersionofconductivity[i–iii],hecouldgiveaqualitativethe-oryoftheWieneffect[iv],andfinallyatheoryofviscosityofelectrolytes[v].TheentiretheorythatevolvedinthegroupofDebyeissometimesreferredtoastheDebye–Hückel–Onsager–Falkenhagentheory(Debye–Hückel–Onsagertheory).Falkenhagenwrotewell-knownbooksandbookchaptersonthetheoryofelectrolytes[iv].Refs.:[i]DebyeP,FalkenhagenH()ZElektrochem:;[ii]FalkenhagenH,DebyeP()PhysZ:;[iii]FalkenhagenH,DebyeP()PhysZ:;[iv]FalkenhagenH,KelbgG()ZElektrochem:;[v]FalkenhagenH()Nature:;[vi](a)FalkenhagenH()Elektrolyte.SHirzel,Leipzig;Engltransl:Falken-hagenH()Electrolytes.Clarendon,Oxford;(b)FalkenhagenH(withcontributionsofEbelingWandHertzHG)()TheoriederElek-trolyte.SHirzel,Leipzig;(c)FalkenhagenH,KelbgG()Thepresentstateofthetheoryofelectrolytes.In:BockrisJO’M,ConwayBE(eds)Modernaspectsofelectrochemistry.Buttersworth,LondonFSFarad—SI-derivedmeasurementunitforcapaci-tance.Symbol:F(namedinhonoroftheBritishphysicistandchemistFaraday).Definition:Acondenserhasthecapacitanceoffarad,whenachargeofcoulombgeneratesavoltageofvolt.F=CV−=CJ−=m−kg−sA.Ref.:[i]CohenER,CvitasT,FreyJG(eds)()IUPACquantities,unitsandsymbolsinphysicalchemistryBMFaradaiccurrentcurrentFaradaicefficiency(orcoulometricefficiency)—Re-latesthemolesofproductformedinanelectrodere-actiontotheconsumedcharge.Thefaradaicefficienc