Construct the Hückel determinants for cyclobutadiene and cyclopentadiene. In what ways are they alike? In what ways are they different?
Interpretation:
The Hückel determinants for cyclobutadiene and cyclopentadiene are to be constructed. The similarities and differences between the two are to be stated.
Concept introduction:
Hückel theory deals with the conjugated systems. In this theory, the
Answer to Problem 15.48E
The Hückel determinant for cyclobutadiene is shown below.
The Hückel determinant for cyclopentadiene is shown below.
The value of overlap integral and the
Explanation of Solution
The structure of the cyclobutadiene is given in figure 1.
Figure 1
The secular determinant for the cyclobutadiene can be written as shown below.
In the above determinant, the overlap integrals
Substitute the value of
The above determinant represents the Hückel determinant for cyclobutadiene.
The structure of the cyclopentadiene is given in figure 2.
Figure 2
The secular determinant for the cyclopentadiene can be written as shown below.
In the above determinant, the overlap integrals
Substitute the value of
The above determinant represents the Hückel determinant for cyclopentadiene.
The value of overlap integral and the
The Hückel determinant for cyclobutadiene is shown below.
The Hückel determinant for cyclopentadiene is shown below.
The value of overlap integral and the
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Chapter 15 Solutions
Physical Chemistry
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