5-silicon ƒe asigɛ siwo ʋẽna lilili siwo wowɔ mlɔeba

Dzɔdzɔmeŋusẽŋununya ƒe Drɔ̃e Si Xɔ Ƒe Alafa Ðeka la Va Do Go

Ƒe alafa ɖeka kple edzivɔe nye sia la, wobu ʋeʋẽ lilili — si nye quantum mechanical phenomenon si naa molecule aɖewo siwo ƒe nɔnɔme le abe asigɛ ene li ke etɔxɛe — be enye carbon ƒe akpa vevitɔ. Benzene, si ŋu woke ɖo le ƒe 1825 me eye August Kekulé kpɔ egbɔ le eƒe xɔtuɖoɖo me le ƒe 1865 me la va zu atike ʋeʋĩwo ƒe nɔnɔmetata ƒe vi, eye atikewɔlawo ƒe dzidzimewo tu dɔwɔƒe blibowo ɖe eƒe xɔtuɖoɖo si wotu ɖe carbon dzi dzi. Gake le nu ɖedzesi aɖe si wowɔ si gbugbɔ ŋlɔ atike si me nugbagbeviwo mele o ƒe sewo me la, numekulawo to asigɛ gbãtɔ si ʋẽna lilili blibo si me nu atɔ̃ le si me silicon atɔmwo katã le la vɛ. Pentasilacyclopentadienide anion sia metsi tre ɖi na aʋadziɖuɖu si wowɔ ko o, ke boŋ kpɔɖeŋu ƒe tɔtrɔ le alesi míesea atikewo ƒe kadodo, molecule ƒe liƒo, kple silicon ƒe ŋutete si womewɔ dɔ tsoe o si wu akpa si wòwɔna le semiconductorwo me gɔme.

Ʋeʋẽ lilili: Liƒo ƒe Nya ɣaɣla si Tu Egbegbe Dzɔdzɔmeŋusẽŋununya

Be nàkpɔ ŋudzedze ɖe nusita silicon-nu ʋeʋĩ ƒe asigɛ le vevie la, ele be nàse nusi ʋeʋẽ lilili nana ŋutɔŋutɔ gɔme gbã. Menye asigɛ ƒe nɔnɔme koe ʋeʋĩ moleculewo le o — elektrɔnik ƒe ɖoɖo tɔxɛ aɖe le wo si afisi pi elektrɔnikwo ƒe teƒeteƒewo woɖena le le asigɛ ƒe wɔwɔme bliboa me, si wɔnɛ be "alilikpo" si me elektrɔnik ƒe kpekpeme si woama si ɖea molecule la ƒe ŋusẽ dzi kpɔtɔna ŋutɔ. Delocalization sia zɔna ɖe Hückel ƒe se dzi, si gblɔ be planar, cyclic molecule si me (4n + 2) pi electrons le — afisi n nye non-negative integer — aɖe ʋeʋẽ lilili afia. Le cyclopentadienide anion (carbon tɔ) gome la, ema fia be pi elektrɔnik 6 siwo ma le carbon atɔm 5 me.

Ŋusẽ sia si naa li ke la menye nu tsɛ o. Benzene, si nye carbon ade ƒe ʋeʋẽ lilili ƒe asigɛ la, li ke abe 150 kJ/mol ene wu alesi wosusui be cyclohexatriene si me kadodo eve le teƒe ɖeka anɔ. Liƒo ma si sɔ gbɔ wue nye nusita atike ʋeʋĩwo xɔ aƒe ɖe atikewo ƒe atikewɔwɔ me (atike siwo dzi woda asi ɖo ƒe 85% kple edzivɔ me ʋeʋĩ ƒe asigɛ ɖeka ya teti le), wowɔa polymers siwo wowɔ ƒe megbeƒu, eye wonyea dometsonu veviwo le dɔwɔƒewo ƒe atikewɔmɔnu siwo ƒe home nye dɔlar biliɔn alafa geɖe ƒe sia ƒe.

Cyclopentadienide anion — carbon ƒe ʋeʋẽ lilili ƒe asigɛ si me akpa atɔ̃ le — nye gɔmeɖoanyi nenema ke. Enye nusi dzi wotu metallocene ƒe atikeŋutinunya ɖo, si na be woate ŋu awɔ nusiwo naa nu ʋãna abe ferrocene ene siwo trɔ asi le organometallic chemistry ŋu le wo didi le wo ŋu le ƒe 1951. Nyabiase si nɔ fu ɖem na atikeŋutinunyalawo ƒe bla nanewo la nɔ tẽ: ne carbon ate ŋu awɔ esia la, nukatae silicon mate ŋui o?

Silicon Mɔxenu: Nusita Nusiwo Kpena Wu Tsi Tre Ðe Ʋeʋẽ lilili Ŋu

Silicon nɔa carbon te tẽ le ɣeyiɣi ƒe kplɔ̃ dzi, ma valence electron ene, eye wòwɔa tetrahedral bonding geometries le compound akpa gãtɔ me. Le pepa dzi la, ele be wòate ŋu awɔ asigɛ siwo ʋẽna lilili. Le nuwɔna me la, silicon ƒe atɔm ƒe didime si lolo wu (1.17 Å tsɔ wu carbon ƒe 0.77 Å) kple 3p ƒe ɣletinyigba siwo kaka wu la wɔa mɔxenu veviwo na axadzi pi-orbital ƒe ƒoƒo ɖe wo nɔewo dzi nyuie si ƒomevi ʋeʋẽ lilili bia.

Wobu silicon-silicon ƒe kadodo eve ŋutɔ be womate ŋu awɔe o vaseɖe esime Robert West ƒe ƒuƒoƒo si le Wisconsin Yunivɛsiti wɔ disilene gbãtɔ si li ke le ƒe 1981. Ɣemaɣi gɔ̃ hã la, kadodo eve siawo gbɔdzɔ kura eye wowɔa dɔ wu wo hati carbon. Si=Si ƒe kadodo eve ƒe ŋusẽ anɔ abe 310 kJ/mol ene ne wotsɔe sɔ kple 614 kJ/mol na C=C. Be woaɖo delocalized pi bonding gbɔ le silicon atɔm ƒe asigɛ blibo aɖe me bia be woaɖu gbɔdzɔgbɔdzɔ sia si le dzɔdzɔme nu dzi esime wole planar geometry si le vevie na orbital overlap la me ɖe asi.

Agbagbadzedze siwo wowɔ va yi le ƒe 40+ me na wokpɔ ʋeʋẽ lilili ƒe asigɛ siwo wotsɔ silicon ɖɔ li ƒe akpa aɖe, heterocycle siwo me silicon le, kple akɔntabubu vovovowo. Gake asigɛ si ʋẽna lilili si ƒe atɔm ɖeka bliboe — atɔm ɖesiaɖe si le asigɛa me nye silicon — gakpɔtɔ nye ƒumelã ɣi si le ƒuƒoƒo veviwo ƒe atikewɔwɔ me. Kuxia nye nu eve: silikon atɔ̃ ƒe asigɛ si me elektrɔnik xexlẽme si sɔ le la wɔwɔ eye woana wòali ke ale gbegbe be wòate ŋu ade dzesi.

Ŋgɔyiyi: Mɔ̃ɖaŋudɔwɔwɔ ƒe Liƒo To Steric Takpɔkpɔ me

Nuwɔwɔ si kpɔ dzidzedze la nɔ te ɖe aɖaŋu aɖe si va zu sika dzidzenu na ƒuƒoƒo vevi siwo wɔa dɔ ƒe liƒo dzi: ƒuƒoƒo siwo ɖɔa li wo nɔewo gãwo. Esi numekulawo ƒe ƒuƒoƒoa tsɔ ligand gã siwo naa elektrɔnik kpe ɖe silicon atɔm ɖesiaɖe si le kɔsɔkɔsɔa me ŋu la, woɖo taɖodzinu vevi etɔ̃ gbɔ le ɣeyiɣi ɖeka me. Ƒuƒoƒo gãawo kpɔ silicon-silicon ƒe kadodo siwo wɔa dɔ la ta ŋutɔŋutɔ tso gotagome nuwɔna gbɔ, woƒe elektrɔnik-nunana ƒe nɔnɔmewo kpe ɖe anion ƒe dzoxɔxɔ manyomanyo ŋu wòli ke, eye woƒe steric bulk zi geometry si gogo-planar si hiã na pi delocalization dzi.

Pentasilacyclopentadienide si wowɔ ƒe dzedzeme ɖo kpe ʋeʋẽ ƒe nɔnɔme dzi to mɔnu geɖe siwo le wo ɖokui si dzi:

ƒe nyawo
• X-ray crystallography ɖe Si-Si ƒe kadodo ƒe didime siwo sɔ kloe fia le asigɛa ŋu (~2.25 Å), si sɔ kple kadodo si me woɖe teƒe bubu tsɔ wu kadodo ɖeka kple eve siwo trɔna
• Nuclear magnetic resonance (NMR) spectroscopy ɖe deshielding ƒe nɔnɔme siwo ɖe dzesi siwo sɔ kple aromatic ring current
fia
• Nucleus-independent chemical shift (NICS) ƒe akɔntabubuwo na asixɔxɔ manyomanyo siwo ɖe dzesi ŋutɔ le ring titina, si nye akɔntabubu ƒe dzesi si dzi ame geɖe da asi ɖo le ʋeʋẽ lilili ŋu
• UV-visible spectroscopy ɖe absorption features siwo sɔ kple delocalized pi-electron transitions le silicon framework
me fia
• Density functional theory (DFT) ƒe akɔntabubuwo ɖo kpe ʋeʋẽ lilili ƒe ŋusẽ gã aɖe dzi, si wobu be enye 50-70 kJ/mol

ƒe nyawo |

Beyond the Lab Bench: Xexeame Ŋutɔŋutɔ ƒe Gɔmesese

Silicon ƒe asigɛ ʋeʋĩwo ƒe wɔwɔme ʋua numekuku ƒe mɔnu siwo keke ta yi ŋgɔ sasasã wu agbalẽnyalawo ƒe didi be yewoanya nu. Silicon-based aromatic compounds ateŋu aɖe elektrɔnik nɔnɔme siwo to vovo kura tso woƒe carbon analogs gbɔ afia, eye woateŋu azã wo le dɔwɔƒe geɖe siwo ƒe asixɔxɔ de ŋgɔ.

Silicon katã ƒe ʋeʋẽ lilili si ŋu woke ɖo la metsɔ atike yeye aɖe kpe ɖe agbalẽdzraɖoƒea ŋu ko o — eɖo molecule ƒe xɔtuɖaŋu ƒe hatsotso yeye kura anyi. Fifia dɔwɔnu ɖesiaɖe si wotu ɖe carbon ƒe ʋeʋẽ lilili dzi le ƒe 160 siwo va yi me la, eƒe kpeɖeŋutɔ si wotu ɖe silicon dzi le lalam be woaku nu me le eŋu, eye wo dometɔ ɖesiaɖe ƒe elektrɔnik, nukpɔkpɔ, kple nusiwo naa nu ʋãna ƒe nɔnɔme siwo ate ŋu anye etɔxɛ.

Le semiconductor mɔ̃ɖaŋununya me, afisi silicon xɔ aƒe ɖe eme xoxo abe gɔmeɖoanyi ene la, silicon ʋeʋẽ lilili ƒe atikewo ate ŋu anye elektrɔnik-nu siwo le molecule ƒe lolome nu. Pi elektrɔnik siwo woɖe ɖe teƒe ɖeka le asigɛ siawo me ate ŋu akplɔ dzoxɔxɔ le mɔ siwo to vovo na silicon gbogbotɔ nu, si ana mɔ siwo yi molecule elektrɔnik kple quantum kɔmpiuta ƒe gɔmeɖoanyiwo gbɔ. Esi wobu akɔnta be xexeame katã ƒe semiconductor ƒe asi agbɔ dɔlar triliɔn ɖeka le ƒe 2030 me ta la, ŋgɔyiyi siwo le dzidzim ɖe edzi le molecule elektrɔnikmɔ̃ siwo wotu ɖe silicon dzi gɔ̃ hã hea asitsatsa ƒe ŋusẽkpɔɖeamedzi gã aɖe vɛ.

Le keklẽŋusẽ me la, silicon ʋeʋẽ lilili ƒe asigɛwo ate ŋu awɔ dɔ abe kekeli-ŋeŋe ƒe chromophores yeyewo ene. Woƒe xɔxlɔ̃ kple dodo ƒe nɔnɔmewo — si woateŋu atrɔ asi le to substituent ƒe tɔtrɔ me — ateŋu ana silicon-based organic light-emitting diodes (OLEDs) alo ɣe ƒe lãmenugbagbeviwo ƒe seselelãme ƒe hatsotso yeyewo nateŋu awɔ vovototo si le silicon fotovoltaic xoxowo kple organic ɣe ƒe mɔ̃ɖaŋununya yeye siwo le dodom dome.

Nyabiase si ʋãa nu: Silicon Metallocenes le Dzomeŋɔli

Ðewohĩ mɔkpɔkpɔ si doa dzidzɔ na ame enumake wue nye ŋutete si le silicon-based metallocenes ŋu. Carbon ƒe cyclopentadienide anion wɔa sandwich-nu siwo me ga ɖesiaɖe kloe si trɔna le, eye metallocene siawo nye nusiwo naa nu ʋãna siwo hiã vevie le polymer ƒe atikewɔwɔ me. Ziegler-Natta kple metallocene catalysts ƒo ƒu doa alɔ polyethylene kple polypropylene tɔn miliɔn 100 kple edzivɔ wɔwɔ ƒe sia ƒe — asi si ƒe home ade dɔlar biliɔn 200.

Ne pentasilacyclopentadienide ateŋu awɔ ɖeka kple tɔtrɔ gawo abe alesi eƒe carbon analog wɔnɛ ene la, silicon metallocenes siwo do tso eme la anye steric kple electronic nɔnɔme siwo to vovo kura. Silicon ƒe asigɛ si lolo wu la ana "bite angle" si keke wu naƒo xlã ga titina, si ate ŋu ana tiatia yeyewo nate ŋu awɔ le olefin polymerization, C-H activation, kple catalytic transformations bubuwo me. Ŋgɔyiyi sue aɖe gɔ̃ hã si wowɔ le nusiwo naa nu ʋãna ƒe dɔwɔwɔ nyuie me le dɔwɔƒewo ƒe dzidzenu sia nu la, eɖea dɔlar biliɔn geɖe ƒe asixɔxɔ gɔme eye woɖea ŋusẽzazã kple gbeɖuɖɔ dzi kpɔtɔna ŋutɔ.

Akɔntabubu ŋuti numekuku gbãtɔwo ɖee fia be silicon metallocenes ateŋu aɖe magnetic nɔnɔme siwo nyo wu hã afia ne wotsɔe sɔ kple wo hati carbon, si aʋu dɔwɔwɔ le spintronics kple magnetic data storage materials me. Agblea nye sɔhɛ, gake wole nukpɔsusu ƒe gɔmeɖoanyia ɖom xoxo le numekuku ƒuƒoƒo geɖewo me le xexeame godoo.

Egbegbe Numekuku Dɔwɔnawo ƒe Sesẽme Dzikpɔkpɔ

| Numekuku ƒuƒoƒowo kple dɔwɔƒe yeye siwo tsɔa woƒe nusiwo ŋu woke ɖo ƒe asitsatsa doa go kuxi siwo tsia tre ɖe dɔwɔƒe ɖesiaɖe si le titina tɔ ŋu: dɔ gbogbo siwo le edzi yim la yometiti, nuƒle kple nudzralawo ƒe ƒomedodowo dzi kpɔkpɔ na atike tɔxɛwo kple dɔwɔnuwo, HR gbɔ kpɔkpɔ na postdocs kple sukunuwula ƒe ƒuƒoƒo siwo trɔna, kple nuŋlɔɖi siwo me kɔ nyuie hena nunya ƒe nunɔamesiwo takpɔkpɔ.

Nuƒolanɔƒewo abe Mewayz ene kpɔa dɔwɔwɔ ƒe kuxi sesẽ sia tututu gbɔ. Esi wònye be modules 207 siwo wotsɔ wɔ ɖekae siwo ku ɖe CRM, invoicing, project management, HR, kple analytics ŋu ta la, Mewayz naa ɖoɖo ɖeka habɔbɔ siwo ŋu numekuku ʋãna be woatsɔ akpɔ asitsatsa ƒe akpa si nye nu yeyewo dodo ɖe ŋgɔ dzi. Le esi teƒe be woatsɔ cobbling ɖekae spreadsheets, email chains, kple disconnected software tools, ƒuƒoƒowo ateŋu akpɔ dɔa ƒe nu veviwo, akpɔ nudzralawo ƒe fexexe dzi na laboratory reagents, awɔ ɖoɖo ɖe ƒuƒoƒo ƒe ɖoɖowɔɖiwo ŋu, eye woawɔ ga ŋuti nyatakaka siwo gadzɔdzɔdɔwɔƒewo bia — wo katã tso mɔnu ɖeka dzi. Le ƒuƒoƒo 138,000+ siwo zãa Mewayz xoxo le xexeame katã gome la, dɔwɔwɔ dzi kpɔkpɔ le teƒe ɖeka sia ƒomevi fia be ɣeyiɣi ʋɛ aɖewo koe woatsɔ awɔ dɔdzikpɔkpɔ ƒe gazazãwo eye ɣeyiɣi geɖe wu atsɔ atutu nusiwo dzɔdzɔmeŋutinunya ate ŋu aɖo ƒe liƒowo.

Nusi Va kplɔe ɖo: Nya ɣaɣla geɖe wu le Periodic Table la

Silicon katã ƒe ʋeʋẽ lilili ƒe asigɛ ƒe wɔwɔme dzidzedzetɔe fɔ biabia sia ɖe te enumake be: Ke Ƒuƒoƒo 14 ƒe nu bubuawo ya ɖe? Germanium, tin, kple lead katã wɔ ɖeka kple silicon ƒe elektrɔnik-valence ene ƒe ɖoɖo, eye wo dometɔ ɖesiaɖe tsɔa eƒe kuxiwo ɖoa ŋkume hena asigɛ ʋeʋĩ ƒe ɖoɖo siwo li ke gbɔ ɖoɖo. Wobu Germanium ƒe ʋeʋẽ lilili ƒe asigɛwo, vevietɔ, fifia be wonye taɖodzinu ŋutɔŋutɔ si woate ŋu aɖo le ɣeyiɣi kpui aɖe me, le germanium ƒe domedome nɔƒe si le silicon kple nusiwo kpekpe wu dome ta.

| dzɔdzɔmeŋutinunyalawo kple atikewɔlawo, siwo wɔa molecule xɔtunu siwo ƒe nɔnɔmewo mate ŋu agbugbɔ awɔ to carbon-based systems ɖeɖeko dzi o.

Pentasilacyclopentadienide ƒe wɔwɔme hã ɖo kpe nɔnɔme si keke ta wu dzi le egbegbe atikeŋutinunya me: ƒuƒoƒo veviwo me dzodzro ɖe ɖoɖo nu hena kadodo ƒe nɔnɔmetata siwo wodzra ɖo ɖi na carbon tsã. Le ƒe blaeve siwo va yi me la, wokpɔ atike siwo li ke siwo me silicon-silicon ƒe kadodo etɔ̃, phosphorus-phosphorus ƒe kadodo etɔ̃, kple boron-boron ƒe kadodo etɔ̃ gɔ̃ hã le la katã va eme. Do ŋgɔ na nusiwo ŋu woke ɖo siawo dometɔ ɖesiaɖe kple agbagbadzedze siwo do kpo nu ƒe bla nanewo kple ɖikeke le nukpɔsusuwo me, eye wo dometɔ ɖesiaɖe ʋu mɔ yeyewo na nuwo ƒe ɖoɖowɔwɔ.

Nusi na silicon ƒe asigɛ si ʋẽna lilili la ɖe dzesi ŋutɔe nye kadodo si le eŋu tẽ kple atikeŋutinunya ƒe nukpɔsusu vevitɔwo dometɔ ɖeka le asitsatsa me. Aromaticity menye agbalẽnyalawo ƒe abstraction o — enye molecule ƒe nɔnɔme si le megbe na atikewo, plastikwo, amadedewo, bɔmb, agblemenukuwo, kple elektrɔniknuwo. Nɔnɔme sia keke ɖe enu ɖe ​​silicon ŋu mewua fli ɖeka nu le nusrɔ̃gbalẽ ƒe kplɔ̃ dzi ko o. Edze silicon ƒe atikeŋutinunya ƒe ɣeyiɣi yeye aɖe gɔme afisi nusi le eme ƒe ŋutete keke ta yi ŋgɔ sã wu kristalo wafer siwo le míaƒe kɔmpiuta ƒe chips me eye wòge ɖe molecule ƒe wɔwɔme ƒe afisi, vaseɖe fifia, nye carbon ɖeɖeko tɔ.

ƒe nyawo

Nyabiase Siwo Wobiana Enuenu

Nukae nye silicon ƒe asigɛ ʋeʋĩ?

Silicon ƒe asigɛ ʋeʋĩ nye molecule si me silicon atɔmwo wɔa xɔtunu si li ke, si le abe asigɛ ene si me "ʋeʋẽ lilili" tɔxɛ aɖe le, nɔnɔme si wosusu ɣeyiɣi didi aɖe be enye carbon ɖeɖeko tɔ. Esia bia be woama elektrɔnikwo ɖe asigɛa ŋu sɔsɔe, si wɔnɛ be wòsẽna le mɔ si mebɔ o nu. Nusi ŋu woke ɖo sia keke ʋeʋẽ ƒe nukpɔsusu ɖe enu vevie wu lãmenugbagbeviwo ƒe dɔwɔwɔ yi nusiwo me agbe mele o abe silicon ene ƒe nuto me.

Nukatae wobua nuƒoƒoƒu sia be enye dzidzedzekpɔkpɔ ɖedzesi aɖe?

Ƒe alafa ɖeka kple edzivɔe nye sia la, ʋeʋẽ lilili nye nɔnɔme si ɖea molecule siwo wotu ɖe carbon dzi abe benzene ene fiana. Asigɛ si li ke, si ʋẽna lilili si wotsɔ silicon wɔe dzidzedzetɔe ɖo kpe edzi be atikeŋutinunya ƒe nukpɔsusu vevi sia menye carbon koŋ tɔ o. Egbugbɔ ŋlɔa nusrɔ̃gbalẽ me sidzedze eye wòʋua mɔnukpɔkpɔ yeye gbogbo aɖewo ɖi na nu yeye siwo ƒe elektrɔnik nɔnɔme tɔxɛ siwo womate ŋu asusu tsã na silicon ƒe ƒuƒoƒo o.

Nukae nye nusiwo woateŋu azã le silicon ƒe asigɛ siawo ŋu?

Esi wogakpɔtɔ le numekuku ƒe gɔmedzedze la, silicon ƒe asigɛ siawo siwo ʋẽna lilili ate ŋu ana woazã wo le tɔtrɔ gã aɖe me. Woate ŋu azã woƒe elektrɔnik wɔwɔme tɔxɛa atsɔ awɔ semiconductor ƒomevi yeyewo, nu deŋgɔ siwo woatsɔ awɔ elektrɔnikmɔ̃wo, alo nusiwo naa nu ʋãna siwo wɔa dɔ nyuie wu. Alesi woaɖu ʋeʋẽ lilili dzi le silicon me gɔmesese ate ŋu aʋu nuwo ŋuti dzɔdzɔmeŋutinunya ƒe alɔdze yeyewo kura, si nye nusɔsrɔ̃ ƒe akpa vevi aɖe na atikeŋutinunyala siwo zãa nunɔamesiwo abe Mewayz (si me modules 207 le le $19/mo).

Aleke nusi ŋu woke ɖo sia do ƒome kple silicon ƒe atikewɔwɔ si li xoxo?

Nu sia si ŋu woke ɖo la tsi tre ɖe nukpɔsusu si nɔ anyi tso blema ke le silicon ƒe atikewɔwɔ ŋu la ŋu. Zi geɖe la, silicon wɔa kadodo ɖeka, si wɔnɛ be kɔsɔkɔsɔwo kple xɔtuɖoɖo siwo ɖi alkanes (haidrodzin siwo me wode nuɖuɖui) wu. Asigɛ ʋeʋĩ si li ke wɔwɔ ɖee fia be silicon ateŋu akpɔ gome le kadodo ƒe ɖoɖo siwo sesẽ wu me, abe carbon ene, si ateŋu ahe silicon-siwo wotu ƒe hatsotso yeye kura vɛ siwo ƒe nɔnɔme to vovo tso silicon kple silane dzɔdzɔewo gbɔ.