Quantum Mechanics Flashcards
De Broglie relationship
Relates wave to particle property
What happens to E as h approaches 0
Energy levels get closer together and there’s no uncertainty in positon and momentum
Heisenberg’s uncertainty principle
Can’t know both position and momentum at the same time
Rules for wavefunctions
Must be a continuous function of x, must have a continuous slope, needs to be normalisable so can’t be infinite
Probability density
Square of wave function
Node
Where wavefunction = 0 and there’s no electron density
Born interpretation
For H atom AO, each wavefunction describes an electron so total electron density over all space = 1
Boundary conditions
Wavefunction must be single-valued as it can’t be in more than one place at once, must be finite as there can’t be an infinite probability of finding te electron and must be continuous
Effects of tunnelling
Effects rate of electron and proton transfer for reactions therefore properties of acids and bases
When is tunnelling more important
For light particles
What must Hamiltonian for hydrogen atom contain terms for
Electron and nucleus kinetic energy in 3D and electron potential energy
How does attraction affect total energy
Stabilises molecule so energy decreases
Why do nodes in orbitals with a higher quantum number have a larger KE
Higher curvature
Number of radial nodes
N-l-1
Number of angular nodes
L
Radial distribution function
Shows probability of finding electron within a given volume
Born-Oppenheimer approximation for H2+
H nucleus much heavier than electron so velocity of nucleus much smaller than an electron so electrons in molecules considered as moving around a set of stationary nuclei, separates total energy of system into Eelectronic and Enuclei
