Qhov Tseem Ceeb Qhov txawv – Lattice vs Unit Cell
Ib lub lattice yog cov qauv tsis tu ncua ua los ntawm ntau lub me me hu ua unit cells. Chav tsev cell yog qhov tsawg tshaj plaws tus neeg sawv cev ntawm ib lub lattice uas muaj tag nrho cov Cheebtsam uas tuaj yeem pom rov ua dua thoob plaws lub lattice qauv. Qhov sib txawv tseem ceeb ntawm cov lattice thiab chav tsev cell yog tias cov lattice yog ib qho kev rov ua peb-dimensional txheej txheem ntawm atoms, ions, los yog molecules nyob rau hauv ib tug hlau los yog lwm yam crystalline khoom whereas ib chav tsev cell yog ib tug yooj yim kev npaj ntawm spheres (atoms, molecules los yog ions.) uas zoo li tus qauv rov ua dua ntawm lub lattice.
Dab tsi yog Lattice?
Ib lub lattice yog ib qho kev rov ua peb-dimensional kev npaj ntawm atoms, ions, los yog molecules nyob rau hauv ib tug hlau los yog lwm yam crystalline khoom. Ib chav cell ntawm lattice sawv cev rau kev rov ua dua ntawm cov lattice; chav tsev cell yog qhov tsawg tshaj plaws nyob rau hauv ib lub lattice uas muaj tag nrho cov tshuaj Cheebtsam nyob rau hauv lub lattice.
Ib lub lattice tuaj yeem tsim tau vim yog covalent bonds ntawm atoms, ionic bonds ntawm ions lossis intermolecular rog ntawm molecules. Ib qho piv txwv ntawm covalent network lattices yog pob zeb diamond. Nyob ntawd, cov pa roj carbon atoms tau sib koom ua ke ntawm covalent bonds, ua rau cov qauv sib txuas. Sodium chloride lattice yog ib qho piv txwv ntawm ionic lattice. Nyob rau ntawd, sodium cations thiab chloride anions yog teem rau hauv ib tug complex network tsim ib tug ionic lattice. Cov dej molecules kuj tuaj yeem tsim ib lub lattice; dej khov. Nyob ntawd, hydrogen bonds ntawm cov dej molecules tuaj yeem ua rau tsim cov lattice uas zoo li cov qauv ntawm pob zeb diamond. Feem ntau ntawm cov hlau kuj tau teem rau hauv cov qauv lattice.
Muaj cov lattice defects nyob rau hauv yuav luag tag nrho cov lattices. Ib qho tsis xws luag yog qhov tsis sib xws hauv lub lattice system. Muaj ob lub ntsiab ntawm cov lattice defects; Frenkel tsis xws luag thiab Schottky tsis xws luag. Hauv Frenkel qhov tsis xws luag, ib qho atom lossis ion nyob rau hauv lub lattice tawm ntawm nws qhov chaw qub thiab nyob ntawm qhov chaw sib txawv hauv tib lub lattice. Ib qho teeb meem Schottky tshwm sim thaum cov ions tawm tsam tawm ntawm lawv qhov chaw qub.
Thaum xav txog cov thermodynamics ntawm ib lub lattice, lub lattice zog yog ib qho kev ntsuas ntawm lub zog uas muaj nyob rau hauv lub siv lead ua lattice ntawm ib tug compound, sib npaug rau lub zog uas yuav tso tawm yog hais tias cov khoom ions raug coj los ua ke los ntawm infinity.
Daim duab 01: Lub Lattice yog ib qho kev hloov pauv ntawm Atoms, Molecules lossis Ions
Muaj 14 hom lattices. Cov ntaub ntawv no yog categorized raws li kev npaj ntawm atoms, molecules los yog ions nyob rau hauv lub chav tsev cell. Cov hom lattice tau muab rau hauv cov lus hauv qab no nrog rau qeb.
Lub Cell yog dab tsi?
Ib chav tsev cell yog ib qho yooj yim kev npaj ntawm spheres (atoms, molecules los yog ions) uas zoo li cov qauv rov ua dua ntawm cov lattice. Ib chav tsev cell raug suav tias yog lub thawv qauv. Lub thawv no muaj tag nrho cov tshuaj lom neeg uas muaj nyob thoob plaws hauv lub lattice. Ib chav tsev ntawm tes yog 3D qauv, thiab nws tau piav qhia siv lattice tsis. Lattice parameters yog qhov ntev ntawm cov npoo thiab cov ces kaum ntawm chav tsev cell.
- ntev nruab nrab ntawm cov npoo ntawm chav tsev cell yog cim los ntawm cov cim a, b thiab c
- lub kaum sab xis ntawm chav tsev cell yog qhia los ntawm cov cim alpha(α), beta(β) thiab gamma(γ)
Daim duab 02: Lattice Parameters
Ib chav tsev ntawm tes tuaj yeem ua tau ntau yam nyob ntawm cov ces kaum thiab qhov ntev ntawm cov npoo ntawm tes. Nws yog lub tsev thaiv ntawm lub lattice. Muaj 7 hom cubic unit cells. Cov npe ntawm cov qauv ntawm tes thiab lawv qhov ntev yog muab rau hauv cov lus hauv qab no.
Kev sib raug zoo ntawm Lattice thiab Unit Cell yog dab tsi?
Ib chav cell yog qhov tsawg tshaj plaws tus neeg sawv cev ntawm ib lub lattice. Nws muab tag nrho cov khoom thiab lawv cov kev npaj uas tau rov ua dua thoob plaws hauv cov qauv lattice
Qhov txawv ntawm Lattice thiab Unit Cell yog dab tsi?
Lattice vs Unit Cell |
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| Ib lub lattice yog ib qho kev ua peb-dimensional rov ua dua ntawm atoms, ions, lossis molecules hauv cov hlau lossis lwm yam khoom siv crystalline. | Ib chav cell yog ib qho yooj yim ntawm kev sib txuas ntawm spheres (atoms, molecules lossis ions) uas zoo li cov qauv rov ua dua ntawm cov lattice. |
| Nature | |
| Lattice yog ib qho loj heev, complex qauv. | chav tsev cell yog qhov yooj yim tshaj plaws thiab tsawg tshaj qhov rov ua dua chav tsev ntawm lub lattice. |
| Number of Atoms | |
| Ib lub lattice muaj ntau tus neeg tsim khoom (atoms, molecules lossis ions). | Ib chav cell muaj tsawg tus neeg suav. |
Summary – Lattice vs Unit Cell
Ib kab laum yog cov qauv sib txuas sib txuas uas muaj cov chav me me txuas rau ib leeg. Cov chav me me no hu ua unit cells. Qhov sib txawv ntawm cov lattice thiab unit cell yog tias ib lub lattice yog ib qho kev ua peb-dimensional rov qab ntawm atoms, ions, los yog molecules nyob rau hauv cov hlau los yog lwm yam crystalline khoom whereas ib chav tsev cell yog ib tug yooj yim kev npaj ntawm spheres (atoms, molecules los yog ions) uas zoo li tus qauv rov ua dua ntawm lub lattice.
