Qhov sib txawv tseem ceeb ntawm kev sib koom ua ke thiab kev sib koom ua ke yog kev sib koom ua ke rov qab yog hais txog kev sib cog lus tshuaj uas tsim los ntawm ib qho atomic orbital ntawm ib lub atom thiab antibonding orbital ntawm lub ligand whereas kev sib koom ua ke yog hais txog kev sib koom ntawm ib khub. electrons ntawm ib hom electronegative thiab ib hom electro-deficient.
Kev sib koom tes sib koom ua ke feem ntau tshwm sim hauv kev sib koom ua ke uas lub hauv paus hlau atom nyob ib puag ncig los ntawm cov ligands, uas tau sib koom nrog cov hlau atom los ntawm kev sib koom tes. Ntawm no, cov ligands qhia lawv ib leeg electron khub nrog cov hlau atom. Tab sis, nyob rau hauv rov qab bonding, ib tug chemical bond tsim ntawm ib tug atomic orbital ntawm ib tug atom thiab ib tug antibonding orbital ntawm lwm atom thaum lawv muaj sib npaug symmetries. Hauv organometallic chemistry, hom tshuaj tiv thaiv kab mob no muaj ntau.
Dab tsi yog Kev Txhaum Rov Qab?
Rov qab sib txuas lossis pi-rov qab kev sib txuas yog qhov xwm txheej uas cov hluav taws xob ntawm lub atomic orbital ntawm ib lub atom txav mus rau qhov kev tiv thaiv kev sib txuas ntawm lwm lub atom, tsim cov tshuaj lom neeg. Ntawm no, ob hom orbitals yuav tsum muaj qhov tsim nyog symmetry. Feem ntau, lub atom nrog lub atomic orbital yog ib qho kev hloov hlau thaum lub atom nrog antibonding orbital yog ib feem ntawm pi-acceptor ligand. Nyob rau hauv organometallic chemistry, hom tshuaj lom neeg daim ntawv cog lus no muaj ntau, thiab nws muaj kev hloov pauv hlau complexed nrog multiatomic ligands, piv txwv li, carbon monoxide, ethylene, nitrosonium ion.
Daim duab 01: Rov qab pub dawb
Ntxiv mus, rov qab kev sib raug zoo yog txheej txheem sib koom ua ke. Nws koom nrog kev pub dawb ntawm cov hluav taws xob los ntawm lub orbital uas muaj cov khoom siv hluav taws xob los yog muaj ib qho hluav taws xob ib leeg rau hauv qhov chaw khoob ntawm cov hlau hloov pauv, ua ke nrog kev tso tawm ntawm cov hluav taws xob los ntawm ib qho d orbital ntawm cov hlau mus rau hauv ib qho antibonding orbital ntawm ligand.
Kev Sib Koom Tes yog dab tsi?
Kev sib koom ua ke yog hais txog cov nyiaj sib koom ua ke uas cov khoom sib koom ua ke tau muab los ntawm ib qho ntawm ob lub atoms hauv daim ntawv cog lus. Qhov ntawd txhais tau tias; Ib lub atom pub ib qho ntawm nws ib leeg electron khub rau lwm lub atom, thiab ib leeg electron khub sib koom ntawm ob lub atom tom qab ntawd. Vim tias nws yog kev pub dawb, peb tuaj yeem hu nws ua daim ntawv cog lus dative lossis dipolar daim ntawv cog lus ib yam nkaus.
Daim duab 02: Txoj Kev Ua Haujlwm Dative Bond Formation
Thaum kos cov qauv tshuaj, peb tuaj yeem qhia qhov sib koom ua ke siv tus xub; lub xub ntiag qhia tau hais tias lub atom txais electrons thiab tus xub tail pib los ntawm lub atom uas pub tus electron khub. Txawm li cas los xij, nws kuj yog ib hom ntawm covalent daim ntawv cog lus; Yog li ntawd, peb hloov cov xub no nrog ib txwm kab los qhia tias nws yog ib daim ntawv cog lus uas ib khub electron sib koom. Cov ntawv cog lus no feem ntau pom nyob rau hauv kev sib koom ua ke uas cov hlau ion txais ib leeg electron khub los ntawm ligands.
Dab tsi yog qhov txawv ntawm Kev Sib Txuas Rov Qab thiab Kev Sib Koom Tes?
Kev sib cog lus rov qab thiab kev sib koom ua ke yog ob qhov sib txawv cov nyiaj sib txawv. Qhov sib txawv tseem ceeb ntawm kev sib koom ua ke rov qab thiab kev sib koom ua ke yog kev sib koom ua ke rov qab yog hais txog cov khoom siv tshuaj lom neeg uas tsim los ntawm ib qho atomic orbital ntawm ib lub atom thiab antibonding orbital ntawm ib lub ligand whereas kev sib koom ua ke yog hais txog kev sib koom ntawm ib khub ntawm electrons ntawm ib hom electronegative. thiab hom kab mob electro-deficient.
Hauv qab infographic qhia qhov sib txawv ntawm kev sib koom ua ke thiab kev sib koom ua ke.
Summary – Back Bonding vs Coordinate Bonding
Kev sib koom ua ke rov qab thiab kev sib koom ua ke yog ob hom kev sib txawv ntawm cov ntawv cog lus. Qhov sib txawv tseem ceeb ntawm kev sib koom ua ke rov qab thiab kev sib koom ua ke yog kev sib koom ua ke rov qab yog hais txog cov khoom siv tshuaj lom neeg uas tsim los ntawm ib qho atomic orbital ntawm ib lub atom thiab antibonding orbital ntawm ib lub ligand whereas kev sib koom ua ke yog hais txog kev sib koom ntawm ib khub ntawm electrons ntawm ib hom electronegative. thiab hom kab mob electro-deficient.
