15-Tema: Atom orbitallarinin` gibridleniwi ha`m molеkulyar orbitallar mеtodlari Reje

The Carbon Molecule (C2)
The carbon atom has the electron configuration 1s22s22p2; thus, there are 12 electrons in the C2 molecule. From the bonding scheme for Li2, we place four additional carbon electrons in the and orbitals. Therefore, C2 has the electron configuration Its bond order is 2, and the molecule has no unpaired electrons. Again, diamagnetic C2 molecules have been detected in the vapor state. Note that the double bonds in C2 are both pi bonds because of the four electrons in the two pi molecular orbitals. In most other molecules, a double bond is made up of a sigma bond and a pi bond.
The Oxygen Molecule (O2)
As we stated earlier, valence bond theory does not account for the magnetic properties of the oxygen molecule. To show the two unpaired electrons on O2, we need to draw an alternative to the resonance structure present on p. 340:
This structure is unsatisfactory on at least two counts. First, it implies the presence
of a single covalent bond, but experimental evidence strongly suggests that there is a double bond in this molecule. Second, it places seven valence electrons around each oxygen atom, a violation of the octet rule. The ground-state electron configuration of O is 1s22s22p4; thus, there are 16 electrons in O2. Using the order of increasing energies of the molecular orbitals discussed above, we write the ground-state electron configuration of O2 as According to Hund’s rule, the last two electrons enter the and orbitals with parallel spins. Ignoring the _1s and _2s orbitals (because their net effects on bonding are zero), we calculate the bond order of O2 using Equation (10.2):
Therefore, the O2 molecule has a bond order of 2 and oxygen is paramagnetic, a prediction that corresponds to experimental observations. Table 10.5 summarizes the general properties of the stable diatomic molecules of
the second period.


Foydalanilgan adabiyotlar:

1. 
   Raymond Chang. General Chemistry: The Essential Concepts. 5 edition, England 2013. 221-233- betlar.
   
2. 
   Парпиев Н.А., Раҳимов Ҳ.Р., Муфтахов А.Г. Анорганик кимё назарий асослари. Т.: Ўзбекистон. 2000. 72-100 бетлар.
   
3. 
   Тошпўлатов Ю.Т., Исҳоқов Ш.С. Анорганик кимё. Т.: Ўқитувчи. 1992. 46-52-бетлар.
   
4. 
   Toshpulatov Yu.T., Raxmatullayev N.G. Anorganik kimyo (nazariy asoslari). T.: TDPU. 2005. 69-73-betlar.
   
5. 
   Аҳмеров Қ., Жалилов А., Сайфутдинов Р. Умумий ва анорганик кимё. Т.: Ўзбекистон. 2003. 61-70 бетлар.
   

1^ General chemistry : the essential concepts / Raymond Chang. – 5th ed

2^General chemistry : the essential concepts / Raymond Chang. – 5th ed

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4^ General chemistry : the essential concepts / Raymond Chang. – 5th ed

5^ General chemistry : the essential concepts / Raymond Chang. – 5th ed