Impeta ya Aromatic 5-silicon ikomatanya nyuma

Ikinyejana cya kera cya Chimie Inzozi Yasohoye

Mu myaka irenga ijana, impumuro nziza - ibintu bya kwantanike itanga imbaraga zidasanzwe kuri molekile zimwe na zimwe zifite impeta - byafatwaga nka karubone yihariye. Benzene yavumbuwe mu 1825 kandi ikemurwa mu buryo na Kanama Kekulé mu 1865, yabaye umwana w’icyapa cy’imiti ihumura neza, kandi ibisekuruza by’imiti yubatse inganda zose ku buryo bwa karuboni. Ariko mubintu byingenzi byagezweho byandika amategeko ya chimie idasanzwe, abashakashatsi bashushanyije impeta yambere yuzuye impumuro nziza igizwe nabantu batanu igizwe na atome ya silicon. Iyi anion ya pentasilacyclopentadienide ntabwo yerekana intsinzi yubukorikori gusa, ahubwo ihindura paradizo muburyo twumva uburyo bwo guhuza imiti, ituze rya molekile, hamwe nubushobozi budakoreshwa bwa silikoni irenze uruhare rwayo mumashanyarazi.

Aromaticity: Ibanga rihamye ryubatse chimie igezweho

Kugirango ushimishe impanvu impeta zose za silicon zifite akamaro, ugomba kubanza kumva icyo aromaticity itanga. Molekile ya Aromatic ntabwo imeze nkimpeta - ifite imiterere yihariye ya elegitoroniki aho pi electroni ziva mubice byose byimpeta, bigakora "igicu" cyubucucike bwa electron bugabanya cyane ingufu za molekile. Uku gutandukana gukurikiza amategeko ya Hückel, avuga ko molekile ya planar, cyclicique hamwe na (4n + 2) pi electron - aho n ari integer itari nziza - izerekana ihumura neza. Kuri anion ya cyclopentadienide (verisiyo ya karubone), bivuze ko electroni 6 pi zisangiwe kuri atome ya karubone 5.

Izi mbaraga zo gutuza ntabwo ari nto. Benzene, impeta ya karuboni itandatu ya karubone, igera kuri 150 kJ / mol ihamye kuruta hypothetical cyclohexatriene hamwe na bonds ebyiri zaba. Ukwo gushikama kwinyongera niyo mpamvu ibice bya aromatic byiganjemo imiti ya farumasi (hejuru ya 85% yimiti yemewe irimo byibura impeta imwe ya aromatic), ikora urufatiro rwimikorere ya polimeri yubukorikori, kandi ikora nkumuhuza wingenzi mubikorwa bya chimique yinganda bifite agaciro ka miliyari amagana yamadorari buri mwaka.

Anion ya cyclopentadienide - impeta ya karubone igizwe nabantu batanu - ni ishingiro. Igize ishingiro rya chimie metallocene, ifasha catalizator nka ferrocene yahinduye chimie organometallic nyuma yo kuvumburwa kwabo mu 1951. Ikibazo cyahigaga abahanga mu bya shimi mumyaka mirongo cyari cyoroshye: niba karubone ishobora gukora ibi, kuki idashobora silikoni?

Inzitizi ya Silicon: Impamvu Ibintu Biremereye Kurwanya Aromaticity

Silicon yicaye munsi ya karubone kumeza yigihe, igabana electroni enye, kandi ikora tetrahedral ihuza geometrike mubice byinshi. Ku mpapuro, igomba kuba ishobora gukora impeta nziza. Mu myitozo, radiyo nini ya atome ya silicon (1.17 Å na karuboni 0,77 Å) hamwe no gukwirakwiza 3p ya orbitale itera inzitizi zifatika muburyo bwiza bwo guhuza pi-orbital ihuza impumuro nziza.

Inkunga ebyiri za Silicon-silicon ubwazo zabonaga ko bidashoboka kugeza igihe itsinda rya Robert West muri kaminuza ya Wisconsin ryashushanyije disilene ya mbere itajegajega mu 1981. Ndetse no muri icyo gihe, ubwo bucuti bubiri bwari bworoshye cyane kandi butitwara neza kurusha bagenzi babo. Ingufu za Si = Si zibiri zingana na 310 kJ / mol ugereranije na 614 kJ / mol kuri C = C. Kugera kuri pilato ya delocalized impeta yose ya atome ya silicon isabwa gutsinda iyi ntege nke mugihe ukomeza planari ya geometrike ikenewe kugirango izenguruke.

Ibigeragezo byabanje kurenza imyaka 40+ byatanze igice cya silicon yasimbujwe impeta yimpumuro nziza, silikoni irimo heterocycle, hamwe nibigereranyo bitandukanye. Ariko impeta yuzuye ya homoatomic - buri atom iri mu mpeta iba silicon - yagumye ari baleine yera ya chimie-matsinda. Ikibazo cyari cyikubye kabiri: guhuza impeta ya silikoni eshanu hamwe numubare wa elegitoronike ukwiye kandi ukagumya guhagarara neza kuranga.

Iterambere: Ihinduka ryubwubatsi binyuze mukurinda Steric

Synthesis igenda neza yishingikirije ku ngamba zahindutse igipimo cya zahabu cyo gutuza ibyingenzi nyamukuru-amatsinda: amatsinda asimbuye. Muguhuza ligande nini, zitanga electron kuri buri atome ya silicon mumuzingo, itsinda ryubushakashatsi ryageze kubintu bitatu byingenzi icyarimwe. Amatsinda manini yarinze umubiri wa silicon-silicon reaction ya reagent yo hanze, imitungo yabo yatanzwe na elegitoronike yafashaga guhagarika amafaranga mabi ya anion, kandi igice kinini cyacyo cyashyize mubikorwa geometrike yegeranye na planari ikenewe kugirango pi delocalisation.

Kuranga pentasilacyclopentadienide ikomatanya yemeje imiterere yimpumuro nziza muburyo bwinshi bwigenga:

• Ibiharuro byigenga bya nucleus byigenga (NICS) kubara byatanze agaciro keza cyane kuri centre yimpeta, ikimenyetso cyemewe cyo kubara cyerekana impumuro nziza
• Ibiharuro bikora (DFT) kubara byemeje ingufu zikomeye zo guhumura neza, zigereranijwe kuri 50-70 kJ / mol

Mugihe ingufu za aromatic stabilisation ziri munsi ya 150 kJ / mol ya benzene, nibyingenzi bihagije kugirango uruganda rutandukane kandi rurangwe nubushyuhe bwicyumba mubihe byubushyuhe bwikirere - ikintu kidasanzwe kuri molekile benshi mubashakashatsi ba chimique bemezaga ko idashobora kubaho muburyo butajegajega.

Kurenga Intebe ya Laboratoire: Ibikorwa-Byukuri-Byisi

Synthesis yimpeta ya silicon impeta ifungura koridoro yubushakashatsi irenze kure amatsiko yamasomo. Ibikoresho bya aromatic bishingiye kuri silicon bishobora kwerekana ibikoresho bya elegitoronike bitandukanye cyane na karuboni zabo, hamwe nibishobora gukoreshwa mu nganda nyinshi zifite agaciro gakomeye.

Ivumburwa rya aromaticity ya silicon yose ntabwo yongeraho gusa ibishya kuri catalog - ishyiraho urwego rushya rwose rwububiko. Porogaramu yose yubatswe kuri aromaticite ya karubone mumyaka 160 ishize ubu ifite mugenzi we ushingiye kuri silikoni utegereje gushakishwa, buri kimwe gifite ibikoresho byihariye bya elegitoroniki, optique, na catalitiki.

Muri tekinoroji ya semiconductor, aho silicon isanzwe yiganje nkibikoresho fatizo, ibice bya aromatic silicon bishobora kuba nkibikoresho bya elegitoroniki. Ibyuma bya elegitoroniki ya delocalized muri izi mpeta birashobora gutwara amafaranga muburyo butandukanye na silikoni nini, itanga inzira igana kuri electronique ya molekuline hamwe na comptabilite ya comptabilite. Hamwe n’isoko rya semiconductor ku isi riteganijwe kurenga tiriyari imwe y’amadolari ya Amerika mu 2030, ndetse n’iterambere ryiyongera mu bikoresho bya elegitoroniki bishingiye kuri silikoni bitwara ibintu byinshi mu bucuruzi.

Muri Photovoltaics, impeta ya aromatic silicon irashobora gukora nka chromofore isarura urumuri. Kwinjiza no gusohora imyuka - ishobora guhindurwa hifashishijwe uburyo bwo guhindura ibintu - irashobora gutuma ibyiciro bishya bya silikoni ishingiye kuri diyode itanga urumuri (OLEDs) cyangwa ibyuma bikoresha ingufu zituruka ku mirasire y'izuba bikuraho itandukaniro riri hagati y’ifoto ya silikoni gakondo hamwe n’ikoranabuhanga rikomoka ku mirasire y'izuba.

Ikibazo cya Catalizike: Silicon Metallocène kuri Horizon

Ahari ibyiringiro byihuse bihita ni ubushobozi bwa metallocène ishingiye kuri silicon. Carion's cyclopentadienide anion ikora ibice bya sandwich hamwe nibyuma byose byinzibacyuho, kandi metallocène ni catalizator ntangarugero muri chimie polymer. Ziegler-Natta na catalizike ya metallocene hamwe bishimangira umusaruro wa toni zisaga miliyoni 100 za polyethylene na polypropilene buri mwaka - isoko rifite agaciro ka miliyari 200 z'amadolari.

Niba pentasilacyclopentadienide ishobora guhuza ibyuma byinzibacyuho nkuko igereranya rya karubone ikora, metallocène ya silicon yavuyemo yaba ifite ibintu bitandukanye muburyo bwa steric na elegitoroniki. Impeta nini ya silicon ishobora gukora "inguni nini" ikikije ikigo cyicyuma, birashoboka ko ishobora guhitamo ibintu bishya muri olefin polymerisation, gukora C-H, hamwe nubundi buryo bwo guhindura ibintu. Ndetse iterambere ryoroheje mubikorwa bya catalizator kuriyi ntera yinganda bisobanura miriyari y'amadorari y'agaciro no kugabanuka gukomeye mu gukoresha ingufu n'imyanda.

Ubushakashatsi bwambere bwo kubara bwerekana ko metallocène silicon ishobora kandi kwerekana imiterere ya magnetiki yongerewe ugereranije na karuboni zabo, gufungura porogaramu muri spintronics hamwe nibikoresho byo kubika amakuru. Umwanya ni muto, ariko ishingiro ryibanze rimaze gushyirwaho mumatsinda menshi yubushakashatsi kwisi yose.

Gucunga ibintu bigoye byubushakashatsi bugezweho

Ibimaze kugerwaho nkimpeta ya silicon impeta yerekana uburemere bwubushakashatsi bwa siyansi bugezweho - imishinga myinshi irimo amatsinda atandukanye, ibikoresho bihenze, kubahiriza amabwiriza, gucunga inkunga, ndetse n’ubufatanye bugenda bwiyongera ku isi. Amatsinda yubushakashatsi hamwe nabatangiye kumenyekanisha ibyo bavumbuye bahura ningorane zikorwa zirwanya iz'uruganda urwo arirwo rwose ruciriritse: gukurikirana imishinga myinshi ikora, gucunga amasoko n’abacuruzi ku miti n’ibikoresho byihariye, gukoresha HR ku matsinda azenguruka amaposita n’abanyeshuri barangije, no kubika inyandiko zuzuye zo kurinda umutungo bwite mu bwenge.

Amahuriro nka Mewayz adresse neza nuburyo bugoye bwo gukora. Hamwe na 207 ihuriweho na CRM, inyemezabuguzi, imicungire yimishinga, HR, hamwe nisesengura, Mewayz iha amashyirahamwe ayobowe nubushakashatsi sisitemu imwe yo gucunga uruhande rwubucuruzi bushya. Aho guhuriza hamwe urupapuro rwabigenewe, iminyururu ya imeri, hamwe nibikoresho bya software bitagabanijwe, amatsinda arashobora gukurikirana ibikorwa byerekana umushinga, gucunga inyemezabuguzi zitanga abaguzi kuri laboratoire, guhuza gahunda zitsinda, no gutanga raporo yimari ibigo bitanga inkunga bisaba - byose biva kumurongo umwe. Ku makipe 138.000+ asanzwe akoresha Mewayz kwisi yose, ubu buryo bwo kugenzura ibikorwa busobanura umwanya muto hejuru yubuyobozi ndetse nigihe kinini cyo guhana imbibi zibyo siyanse ishobora kugeraho.

Ibizakurikiraho: Imbonerahamwe yigihe ifite amabanga menshi

Synthesis igenda neza yimpeta ya silicon yose ya aromatic ihita itera ikibazo: tuvuge iki mubindi bice 14 bigize itsinda? Ubudage, amabati, hamwe no kuyobora byose bisangiye silicon ya bine-valence-electron, kandi buriwese agaragaza imbogamizi zazo kugirango agere kuri sisitemu yimpeta ihamye. Impeta ya aromatic ya Germanium, ubu, ifatwa nkintego ifatika mugihe gito, urebye umwanya wa germanium uri hagati ya silicon nibintu biremereye.

Hanze y'itsinda rya 14, igitekerezo cya aromaticity kimaze kwaguka kugeza kuri classe ya boron (borane na karbone byerekana aromaticité-eshatu), impeta ya fosifore, ndetse na sisitemu ya aromatique yose ya metero nka tetraanion ya Al4²⁻ tetraanion yaranzwe bwa mbere muri 2001. Buri kintu gishya kigera kubintu byubaka umubiri hamwe na sisitemu yubumenyi bwa karubone. wenyine.

Synthesis ya pentasilacyclopentadienide nayo yemeza inzira yagutse muri chimie ya kijyambere: ubushakashatsi butunganijwe bwibice-byingenzi bigize amatsinda yo guhuza moteri yabigenewe mbere ya karubone. Mu myaka 20 ishize, ibice bihamye birimo silikoni-silikoni inshuro eshatu, fosifore-fosifore inshuro eshatu, ndetse na boron-boron inshuro eshatu zose zaragaragaye. Buri kimwe muri ibyo byavumbuwe cyabanjirijwe n’imyaka mirongo yo kugerageza kunanirwa no gushidikanya ku nyigisho, kandi buriwese yafunguye inzira nshya zo gushushanya ibikoresho.

Igituma impeta ya silicon impumuro nziza cyane ni ihuza ryayo na kimwe mubintu bya chimie byingenzi mubucuruzi. Aromaticity ntabwo ari abstraction yubumenyi - ni umutungo wa molekuline ushigikira imiti, plastiki, amarangi, ibisasu, imiti y’ubuhinzi, nibikoresho bya elegitoroniki. Kwagura uyu mutungo kuri silicon ntabwo byuzuza gusa umurongo kumeza yigitabo. Itangiza ibihe bishya bya chimie ya silicon aho ubushobozi bwibintu bugera kure cyane ya waferi ya kristaline muri chip ya mudasobwa yacu no mubice byashushanyijemo molekile, kugeza ubu, byari ibya karubone gusa.