Lecture 1: Intro Flashcards
What is a theory?
One or more rules that are postulated to govern the behaviour of a system
What is a model
Deliberate approximations of a general theory for practical utility
What is computation
Use of digital technology to solve mathematical equations behind theory/model
What does the potential energy surface show?
Potential energy as a function of relative positions of all atoms
Why do we need to know about the PES?
It contains info about reaction rates, processes, and transition states
What does PES not show?
Kinetic energy
What does a valley in a PES show?
Low energy state
What does a saddle point on a PES show?
Transition state
What does a mountain on a PES show?
Activation energy
What does the Born-Oppenheimer Approximation assume?
That wave functions of atomic nuclei and electrons can be treated separately because nuclei are much heavier than electrons
How many times heavier are nuclei compared to electrons?
1838 x electron mass
Why is BO approximation important in comp chem?
Allows us to consider electronic structure and atomic positions separately
