Bonding vs Antibonding Molecular Orbitals
Qhov txawv ntawm kev sib txuas thiab kev tiv thaiv kab mob molecular orbitals tuaj yeem piav qhia tau zoo tshaj plaws siv "Molecular orbital theory." Ob hom molecular orbitals no yog tsim thaum covalent tshuaj bonds raug tsim. Qhov sib txawv tseem ceeb tshaj plaws ntawm kev sib txuas thiab kev tiv thaiv kab mob molecular orbitals yog lawv cov qib zog piv rau niam txiv atomic orbitals. Qhov sib txawv ntawm lub zog no ua rau lwm qhov sib txawv ntawm ob lub cev molecular.
Bonding thiab antibonding molecular orbitals yog tsim los ntawm linear ua ke atomic orbitals. Cov ntsiab lus tseem ceeb hauv qab no tseem ceeb heev, kom nkag siab qhov sib txawv ntawm kev sib txuas thiab kev tiv thaiv kab mob molecular orbitals.
Aufbau txoj cai - orbitals nrog lub zog qis tshaj plaws tau sau ua ntej.
Pauli cais txoj cai - Qhov siab tshaj plaws ntawm cov hluav taws xob (nrog rau qhov sib txawv) uas tuaj yeem tuav lub orbital yog ob.
Hund txoj cai - Thaum muaj ob peb Molecular Orbitals nrog lub zog sib npaug, cov electrons tuav lub Molecular Orbitals ib zaug ua ntej ob tus nyob hauv tib lub Molecular Orbital.
Dab tsi yog Bonding Molecular Orbitals?
Kev sib txuas molecular orbitals yog tsim los ntawm atomic orbitals los ntawm theem ua ke ntawm atomic orbitals. Nws tsub kom cov electron ceev ntawm bonded atoms. Lawv lub zog qis dua lub atomic orbitals. Electrons yog thawj zaug sau rau hauv kev sib txuas molecular orbitals thiab lawv stabilize lub molecule vim lawv koom nrog tsawg zog dua li cov electron nyob rau hauv niam txiv atom.
Molecular orbital daim duab rau Hydrogen
Dab tsi yog Antibonding Molecular Orbitals?
Antibonding molecular orbitals yog tsim los ntawm kev sib xyaw ua ke ntawm atomic orbitals thiab nws txo qis electron ceev ntawm ob lub atoms. Nyob rau hauv antibonding molecular orbitals, lub zog yog siab tshaj lub atomic orbitals uas tsim lawv. Vim qhov tseeb no, thaum electrons tau ntim rau hauv cov tshuaj tiv thaiv molecular orbitals, nws destabilizes daim ntawv cog lus ntawm ob lub atoms.
H2 1sσ antibonding molecular orbital
Qhov txawv ntawm Bonding Molecular Orbitals thiab Antibonding Molecular Orbitals yog dab tsi?
Zog:
ENERGYAntibonding molecular orbitals > ENERGY Bonding molecular orbitals
• Bonding molecular orbitals muaj zog qis dua piv rau niam txiv atomic orbital.
• Antibonding molecular orbitals muaj lub zog siab dua li ntawm niam txiv atomic orbitals.
• Feem ntau, cov khoom siv hluav taws xob thawj zaug tau ntim rau hauv qis zog. Yog li ntawd, cov electrons yog thawj zaug sau rau kev sib txuas molecular orbitals thiab tom qab ntawd mus rau antibonding molecular orbitals.
Kev ruaj ntseg:
• Bonding molecular orbitals ruaj khov dua ob qho tib si antibonding molecular orbitals thiab niam txiv atomic orbital.
• Antibonding molecular orbitals tsis ruaj khov dua ob qho tib si sib txuas molecular orbitals thiab niam txiv atomic orbtials.
• Qhov laj thawj tseem ceeb rau qhov sib txawv ntawm kev ruaj ntseg yog qhov sib txawv ntawm lub zog. Qhov siab dua lub zog yog tsawg dua yog stability. Lub zog qis dua yog qhov ruaj khov.
Electron Muaj:
• Qhov tshwm sim ntawm kev nrhiav ib qho hluav taws xob yog siab heev hauv kev sib txuas molecular orbitals.
• Nrhiav ib qho hluav taws xob hauv cov tshuaj tiv thaiv molecular orbitals yog qhov tsawg kawg nkaus.
Kev pab txhawb rau cov duab ntawm cov molecule:
• Bonding molecular orbitals ncaj qha ua rau cov duab ntawm cov molecule.
• Antibonding molecular orbitals tsis ua rau cov duab ntawm cov molecule.
