PhononThermo.py

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PhononThermo.py

• B. Fultz
• August 2003
• Calculate thermodynamic functions from phonon DOS
  data

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ASCII Data Files on Disk (DOS reduced from
Pharos Data)

• ltPuDOS.pygt
• header "Energy", "Intensity", "Error"
• table 0.0, 0.0, 0.0,
• 0.075, 0.026478, 0.01150,
• 0.225, 0.083316, 0.02041,
• 0.375, 0.11699235, 0.02418,

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Data Structures 2 -- Add Temperature
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Disk File Data Temperature Series

• ltEXdict.pygt
• ...
• Pu150K 0.0, 0.0, 0.0 , 0.25, 0.121, 0.0 ,
  ... , 32.0, 3.47, 0.0
• Pu300K 0.0, 0.0, 0.0 , 0.25, 0.041, 0.0 ,
  ... , 32.0, -5.55, 0.0
• temperature 15.0, 65.0, 150.0, 300.0
• header 'Energy', 'Intensity', 'Error'
• Xdict 'temperature' temperature,
  'header'header, '15.0'Pu15K, '65.0'Pu65K,
  '150.0'Pu150K, '300.0'Pu300K

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Internal Data Structures Arbitrary Temperature
g_params slope0, intercept0, E0, slope1,
intercept1, E1, slope2, intercept2, E2 ...
pDOS T triplet0 triplet1 E
triplet2
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My Program Control (old)
def S_harm j0 S0 normaliz 0 while j lt
DOSpoints Prior operation calculated length
of Energylist if (temperature ltgt 0.0 and
float(Energylistj) ltgt 0.0) energy
float(Energylistj) DOS float(DOSlistj)
S S DOS S_mode(energy, temperature) norm
aliz normaliz DOS jj1 else jj1
return Entropy S/normaliz
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My Program Control (new)
S 0 normaliz 0 for pair in DS.gE
Nested list pair0 is DOS, pair1 is
Energy pDOS pair0 E pair1 if (T
ltgt 0.0 and E ltgt 0.0 and E lt E_cutoff) S
pDOS SF.S_mode(E,T) normaliz
pDOS S_harm self.data S/normaliz return
S_harm
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Functions
Bose-Einstein factor def BE(E,T) n 1 / (
math.exp(E/T) - 1 ) return n
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Functor Design (objects that are functions)
Quadratic.py class Quadratic def
__init__(self, A, B, C) self.A A self.B
B self.C C return def __eval__(self,
x) return self.Ax2 self.Bx self.C
Calculates Ax2 Bx C
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Use the Functor
import Quadratic, math instantiate
functor quad Quadratic.Quadratic(A1.0, B0.0,
C0.0) evaluate parametrically for i in
range(10) print i, quad.__eval__(i)
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Classes of PhononThermo.py

• class DOS "A single DOS from one measurement."
• class DOS_qh "Parameters for T-dependent DOS are
  constructed from data at different temperatures.
• class StandardFunction "Phonon thermodynamic
  functions that depend on DOS(E), P, T"
• BE(E,T) is the Bose-Einstein factor.
• This S_mode(E,T) has the elegant form
  developed .
• This S_osc(E,T) was developed by Max Planck
• class S_harm "Phonon entropy in the harmonic
  approx."
• class E_harm "Phonon energy in the harmonic
  approx."
• class E_quasi "Phonon energy in the
  quasiharmonic approx."
• class E_quasi "Phonon energy in the
  quasiharmonic approx."
• class S_anh "Anharmonic phonon entropy."
• class E_anh "Anharmonic phonon energy."

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Modules
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• End of Presentation

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Supporting Modules.py -- old

• ReadMultipleFiles.py
• Scans file names to find all temperatures
• Simple files of all independent data
• ReadColumn.py
• Counts ltCRgt
• Counts Words in File
• Figures out Number of Columns

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ASCII Data Files on Disk -- old style (DOS
reduced from Pharos Data)

• Pu_Temp_Data/
• Pu77_E.dat Pu77_I.dat
• Energy_1ltCRgt Intensity_1ltCRgt
• Energy_2ltCRgt Intensity_2ltCRgt
• Energy_3ltCRgt Intensity_3ltCRgt
• . .
• . .
• . .