Formulas Flashcards
How do you find v (frequency)?
v= c/ wavelength
Remember speed frequents wave
How do you find E (energy) of one photon?
E=hv
Remember E hates V
How do you find E (energy) of one mole of photons?
E= Na x hv
How do you find v~ (wavenumber)?
V~= 1/wavelength x 100
How do you find the energy of the energy gap?
^E= hv
How do you find transmission and percentage transmission?
T= I/Io
x 100%
How do you find absorption?
A= log(Io/I) = Ecl
How do you find the moment of inertia?
I= RM x r^2
How do you find reduced mass?
RM= mA x mB/ mA+ mB
How do you find rotational energy E?
E= 1/2 I (angular velocity)^2
How do you find the energy of a rotational energy level J?
- energy of a particular level
EJ= B J(J+1)
Where J=0,1,2,3…
B is the rotational constant
How do you calculate the rotational constant B
- depends on the molecule
B= h/ 8pi^2 x I x c
How do you find the energy gap between one rotational energy level and the next one?
^EJ->J+1= 2B(J+1)
How are the formulas form the energy of the J levels and the energy gap between the levels altered for a non rigid diatomic?
The more it rotates the more it stretches
EJ= BJ(J+1) -DJ^2(J+1)^2 ^EJ= 2B(J+1) -4D (J+1)^3
D is the centrifugal distortion constant
How do you calculate vibrational frequency?
Vvib- vibrational frequency
Vvib= 1/2pi {k/RM}
How do you calculate vibrational wavenumber?
V~vib= vibrational wavenumber
V~vib= Vvib/c
= 1/2piC x {k/RM}
How do you calculate the energy of a vibrational energy level?
Ev= (v+1/2) v~vib
How do you calculate the energy gap between one vibrational energy level and the next?
^Ev->v+1= V~vib
What is Etotal?
Etotal= Ev + EJ
How do you calculate EvJ?
EvJ= v~obs= v~vib +/- 2Bm
How do you work out the number of vibrational modes for a linear and non linear molecule?
Non linear
3N-6
Linear
3N-5
How do you calculate Aobs?
Aobs= Aa + Ab…
What is the v~stokes equation?
Loses energy
V~stokes= v~ex -^v~
The incident photon experiences a change in wavenumber
What is the v~ antistokes equation?
Gains energy
V~antistokes= v~ex +^v~
The incident photon experiences a change in wavenumber
