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Atomic Line Width

TK Solver Model for Atomic Line Width, including Doppler and collisional (pressure) broadening.

d = Doppler, c = collisional, line = Voigt

Variable sheet:

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St Input     Name    Output    Unit      Comment                                
   324.7     Wo                nm        wavelength of line center
             fo      92392.978 cm-1      frequency of line center
   3000      T                 K        Temperature                            
   63.5      A                 amu       atomic weight of atom             
   28        M                 amu       molecular weight of collider      
   220       sigmaa            A2        cross section, defined as r^2 (square A)
             DLaColl 1.0878596 pm        adiabadic collision width (wavelength)
             DNuColl 3.09549E9 sec-1     adiabadic collision width (frequency)
             DLaDop  1.5973406 pm        Doppler width (wavelength)
             DNuDop  4.54521E9 sec-1     Doppler width (frequency)
             DLaVoi  2.231341  pm        Voigt width (wavelength)
             a       .56700649           a parameter or damping factor 
             N       2.445E18  cm-3      number density of colliders  (cm-3)
   1         P                 atm       Pressure of colliders       
                    19.431694 amu       Reduced mass of atom-collider pair
             v       180792.48 cm/sec    Mean velocity of atom-collider pair
             shift   2.21106E9 sec-1     red shift  
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Rule sheet.
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c=3e10                                     "Speed of light, cm/sec
k=1.38E-16                                 "Boltsmann's constant, erg/K
R=83140000                                 "Gas constant, ergs/mol/K
DNuDop=3E10*DLaDop/(Wo*Wo)
DNuDop=(1/Wo)*Sqrt(ln(2))*Sqrt((8*R*T)/A)
Wo*fo=3E10
DNuColl=v*sigmaa*N/Pi()
DNuColl=3E10*DLaColl/(Wo*Wo)
N=.001*6.022e23*P/(T*0.0821)
a=DNuColl*Sqrt(ln(2))/DNuDop              "Definition of a parameter or damping factor
=1/(1/A+1/M)                             "Reduced mass of atom-collider pair, amu
v=Sqrt(8*R*T/(Pi()*))                    "mean velocity of atom-collider pair, cm/sec
DLaVoi=DLaColl/2+Sqrt((DLaColl/2)^2+DLaDop^2)
shift=DNuColl/1.4
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T. C. O'Haver, Chem 623, 1994