How Do Basis Vectors Represent Orbitals in Quantum Chemistry?

  • Thread starter Thread starter Niles
  • Start date Start date
  • Tags Tags
    Quantum
Click For Summary
SUMMARY

This discussion focuses on the interpretation of basis vectors in quantum chemistry, specifically in the context of orbitals represented by orthonormal states |1>, |2>, |3>, |4>, |5>, and |6>. The user questions how these basis vectors can represent orbitals if they do not correspond to stationary states of the system, as defined by the time-independent Schrödinger equation. The conclusion drawn is that while these basis vectors span the Hilbert space, they serve as a framework for constructing eigenstates through linear combinations, which can possess associated eigenenergies.

PREREQUISITES
  • Understanding of the Schrödinger equation in quantum mechanics
  • Familiarity with Dirac notation and Hilbert spaces
  • Knowledge of eigenstates and eigenenergies in quantum systems
  • Basic concepts of linear combinations in vector spaces
NEXT STEPS
  • Study the implications of linear combinations of basis vectors in quantum mechanics
  • Explore the concept of orthonormality in Hilbert spaces
  • Research the role of eigenstates in quantum chemistry
  • Learn about the physical interpretation of orbitals in molecular systems
USEFUL FOR

Students and researchers in quantum chemistry, particularly those studying molecular orbitals and the mathematical framework of quantum mechanics.

Niles
Messages
1,834
Reaction score
0

Homework Statement


Hi all.

This post is about quantum chemistry, but my question arises when looking at the problem from a physical point of view.

The Schrödinger equation gives us the stationary states of a system, and let's say that we are looking at a system with two stationary states (Dirac notation - but the LaTeX does not work, so bear with me) |1> and |2> with an associated eigenenergy. These two orthonormal states span the Hilbert space we are working in.Now here's my question: I am looking at a figure of a molecule with six orbitals, and now each orbital is represented by an orthonormal basis |1>, |2>, |3>, |4>, ..., |6>. An eigenstate is then a linear combination of these basis-vectors (orbitals) with an associated energy.

Question: How am I do interpret these basis-vectors |1>, |2>, |3>, |4>, ..., |6>? They surely cannot represent stationary states (i.e. solutions to the time-independent Schrödinger equation), because then a linear combination of them would not have an eigenenergy.

Thanks in advance. Any help will be greatly appreciated, since I cannot get help from anywhere else at the moment.Niles.
 
Physics news on Phys.org
Can I get a moderator to move this thread to the "Advanced Physics Homework Help"? I think it belongs there more than in this section.

Thanks in advance.
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 61 ·
3
Replies
61
Views
6K
  • · Replies 16 ·
Replies
16
Views
1K
  • · Replies 0 ·
Replies
0
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K