How do I properly normalize a wave function with given real functions?

Click For Summary

Homework Help Overview

The discussion revolves around normalizing a wave function in the context of physical chemistry, specifically involving three given real functions that are stated to be normalized and orthogonal. The original poster presents a function that combines these wave functions and seeks guidance on how to properly normalize it.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to clarify the normalization process and questions the integration range due to a lack of specified x values. Participants inquire about the correctness of the original poster's approach and suggest using LaTeX for clarity.

Discussion Status

Participants are engaged in exploring the normalization condition and the integration process. Some have pointed out potential issues with the expression's format and the need to evaluate the integral correctly. There is an ongoing clarification regarding the integration of the entire expression for normalization.

Contextual Notes

There is a mention of the normalization condition requiring an integral over the wave function squared, but the original poster is uncertain about the integration limits and whether they are applying the normalization correctly. The discussion reflects a lack of consensus on the interpretation of the function's setup.

ReidMerrill
Messages
65
Reaction score
2

Homework Statement


"assume that the three real functions ψ1,ψ2, and ψ3 are normalized and orthogonal. Normalize the following function"

ψ1 - ψ21/(sqrt2) + ψ3sqrt(3)/sqrt(6)

Homework Equations


This is for a physical chemistry class. I haven't seen an example like this. All that is in our textbook is that integral[ /ψ/2dT] needs to equal 1 which is accomplished by adjusting N so N2 Integral[ /ψ/2dx] =1

The Attempt at a Solution


Is this correct? What range do I integrate it over? no x values are given.Any help will be greatly appreciated!
[/B]
 
Physics news on Phys.org
ReidMerrill said:

Homework Statement


"assume that the three real functions ψ1,ψ2, and ψ3 are normalized and orthogonal. Normalize the following function"

ψ1 - ψ21/(sqrt2) + ψ3sqrt(3)/sqrt(6)

Homework Equations


This is for a physical chemistry class. I haven't seen an example like this. All that is in our textbook is that integral[ /ψ/2dT] needs to equal 1 which is accomplished by adjusting N so N2 Integral[ /ψ/2dx] =1

The Attempt at a Solution

[/b]
Is this correct? What range do I integrate it over? no x values are given.
Is what correct? You haven't shown any work.

The readability of your post would improve if you use LaTeX. Here's a primer: https://www.physicsforums.com/help/latexhelp/.
 
vela said:
Is what correct? You haven't shown any work.

The readability of your post would improve if you use LaTeX. Here's a primer: https://www.physicsforums.com/help/latexhelp/.
I don't know why all my subscripts disappeared.

ψ1 - ψ2 1/(sqrt6) + ψ3 sqrt(3)/sqrt(6)

In the book it says that to normalize a function you need to adjust N so that
N2 Integral [/ψ/2 dx] =1

I don't know how I'd apply that to this question
 
In this problem, you have ##\psi(x) = N\left(\psi_1 - \frac{1}{\sqrt{6}} \psi_2 + \frac{\sqrt{3}}{\sqrt{6}}\psi_3\right)##. (Are you sure about that state? It's written a bit strangely, i.e., ##\sqrt{3}/\sqrt{6} = 1/\sqrt{2}##.)
 
vela said:
In this problem, you have ##\psi(x) = N\left(\psi_1 - \frac{1}{\sqrt{6}} \psi_2 + \frac{\sqrt{3}}{\sqrt{6}}\psi_3\right)##. (Are you sure about that state? It's written a bit strangely, i.e., ##\sqrt{3}/\sqrt{6} = 1/\sqrt{2}##.)

That's how it's written in the book.

Since x isn't in the function
vela said:
In this problem, you have ##\psi(x) = N\left(\psi_1 - \frac{1}{\sqrt{6}} \psi_2 + \frac{\sqrt{3}}{\sqrt{6}}\psi_3\right)##. (Are you sure about that state? It's written a bit strangely, i.e., ##\sqrt{3}/\sqrt{6} = 1/\sqrt{2}##.)

That's just how it's written. So when I integrate that with respect to x i get N(ψ1 - ψ2 1/(sqrt6) + ψ3 sqrt(3)/sqrt(6))x +C
Did I integrate that correctly? And if so what do I do from here?
 
Remember that ##\psi_1##, ##\psi_2##, and ##\psi_3## are functions of ##x##. You said the normalization condition is
$$\int_{-\infty}^\infty \psi^2\,dx = 1.$$ You want to substitute the expression you're given for ##\psi## and evaluate the integral.

Think about what it means when you're told that the ##\psi_i##'s are normalized and orthogonal to each other.
 
vela said:
Remember that ##\psi_1##, ##\psi_2##, and ##\psi_3## are functions of ##x##. You said the normalization condition is
$$\int_{-\infty}^\infty \psi^2\,dx = 1.$$ You want to substitute the expression you're given for ##\psi## and evaluate the integral.
Ohhh! I did it as an indefinite integral. So, just to clarify, I need to plug in the whole original equation into the integral?
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 9 ·
Replies
9
Views
5K
  • · Replies 1 ·
Replies
1
Views
8K
Replies
7
Views
2K
  • · Replies 8 ·
Replies
8
Views
12K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 33 ·
2
Replies
33
Views
8K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 14 ·
Replies
14
Views
3K