# -*- coding: utf-8 -*-
# BioSTEAM: The Biorefinery Simulation and Techno-Economic Analysis Modules
# Copyright (C) 2020, Yoel Cortes-Pena <yoelcortes@gmail.com>
#
# A significant portion of this module originates from:
# Chemical Engineering Design Library (ChEDL). Utilities for process modeling.
# Copyright (C) 2020 Caleb Bell <Caleb.Andrew.Bell@gmail.com>
#
# This module is under a dual license:
# 1. The UIUC open-source license. See
# github.com/BioSTEAMDevelopmentGroup/biosteam/blob/master/LICENSE.txt
# for license details.
#
# 2. The MIT open-source license. See
# https://github.com/CalebBell/thermo/blob/master/LICENSE.txt for details.
"""
All data and methods for estimating a chemical's refractivity.
"""
import os
import pandas as pd
from .._constants import N_A, pi
__all__ = ['CRC_RI_organic', 'RI_methods', 'refractive_index',
'polarizability_from_RI', 'molar_refractivity_from_RI',
'RI_from_molar_refractivity']
folder = os.path.join(os.path.dirname(__file__), 'Data/Misc')
CRC_RI_organic = pd.read_csv(os.path.join(folder, 'CRC Handbook Organic RI.csv'),
sep='\t', index_col=0)
CRC = 'CRC'
NONE = 'NONE'
RI_methods = [CRC]
[docs]def refractive_index(CASRN, T=None, AvailableMethods=False, Method=None,
full_info=True):
r'''
This function handles the retrieval of a chemical's refractive
index. Lookup is based on CASRNs. Will automatically select a data source
to use if no Method is provided; returns None if the data is not available.
Function has data for approximately 4500 chemicals.
Parameters
----------
CASRN : string
CASRN [-]
Returns
-------
RI : float
Refractive Index on the Na D line, [-]
T : float, only returned if full_info == True
Temperature at which refractive index reading was made
methods : list, only returned if AvailableMethods == True
List of methods which can be used to obtain RI with the given inputs
Other Parameters
----------------
Method : string, optional
A string for the method name to use, as defined by constants in
RI_methods
AvailableMethods : bool, optional
If True, function will determine which methods can be used to obtain
RI for the desired chemical, and will return methods instead of RI
full_info : bool, optional
If True, function will return the temperature at which the refractive
index reading was made
Notes
-----
Only one source is available in this function. It is:
* 'CRC', a compillation of Organic RI data in [1]_.
Examples
--------
>>> refractive_index(CASRN='64-17-5')
(1.3611, 293.15)
References
----------
.. [1] Haynes, W.M., Thomas J. Bruno, and David R. Lide. CRC Handbook of
Chemistry and Physics, 95E. Boca Raton, FL: CRC press, 2014.
'''
def list_methods():
methods = []
if CASRN in CRC_RI_organic.index:
methods.append(CRC)
methods.append(NONE)
return methods
if AvailableMethods:
return list_methods()
if not Method:
Method = list_methods()[0]
if Method == CRC:
_RI = float(CRC_RI_organic.at[CASRN, 'RI'])
if full_info:
_T = float(CRC_RI_organic.at[CASRN, 'RIT'])
elif Method == NONE:
_RI, _T = None, None
else:
raise Exception('Failure in in function')
if full_info:
return _RI, _T
else:
return _RI
[docs]def polarizability_from_RI(RI, Vm):
r'''
Returns the polarizability of a fluid given its molar volume and
refractive index.
.. math::
\alpha = \left(\frac{3}{4\pi N_A}\right)
\left(\frac{n^2-1}{n^2+2}\right)V_m
Parameters
----------
RI : float
Refractive Index on Na D line, [-]
Vm : float
Molar volume of fluid, [m^3/mol]
Returns
-------
alpha : float
Polarizability [m^3]
Notes
-----
This Lorentz-Lorentz-expression is most correct when van der Waals
interactions dominate. Alternate conversions have been suggested.
This is often expressed in units of cm^3 or Angstrom^3. To convert to these
units, multiply by 1E9 or 1E30 respectively.
Examples
--------
>>> polarizability_from_RI(1.3611, 5.8676E-5)
5.147658123614415e-30
References
----------
.. [1] Panuganti, Sai R., Fei Wang, Walter G. Chapman, and Francisco M.
Vargas. "A Simple Method for Estimation of Dielectric Constants and
Polarizabilities of Nonpolar and Slightly Polar Hydrocarbons."
International Journal of Thermophysics 37, no. 7 (June 6, 2016): 1-24.
doi:10.1007/s10765-016-2075-8.
'''
return 3/(4*pi*N_A)*(RI**2-1)/(RI**2+2)*Vm
[docs]def molar_refractivity_from_RI(RI, Vm):
r'''
Returns the molar refractivity of a fluid given its molar volume and
refractive index.
.. math::
R_m = \left(\frac{n^2-1}{n^2+2}\right)V_m
Parameters
----------
RI : float
Refractive Index on Na D line, [-]
Vm : float
Molar volume of fluid, [m^3/mol]
Returns
-------
Rm : float
Molar refractivity [m^3/mol]
Notes
-----
Examples
--------
>>> molar_refractivity_from_RI(1.3611, 5.8676E-5)
1.2985217089649597e-05
References
----------
.. [1] Panuganti, Sai R., Fei Wang, Walter G. Chapman, and Francisco M.
Vargas. "A Simple Method for Estimation of Dielectric Constants and
Polarizabilities of Nonpolar and Slightly Polar Hydrocarbons."
International Journal of Thermophysics 37, no. 7 (June 6, 2016): 1-24.
doi:10.1007/s10765-016-2075-8.
'''
return (RI**2 - 1.)/(RI**2 + 2.)*Vm
[docs]def RI_from_molar_refractivity(Rm, Vm):
r'''
Returns the refractive index of a fluid given its molar volume and
molar refractivity.
.. math::
RI = \sqrt{\frac{-2R_m - V_m}{R_m-V_m}}
Parameters
----------
Rm : float
Molar refractivity [m^3/mol]
Vm : float
Molar volume of fluid, [m^3/mol]
Returns
-------
RI : float
Refractive Index on Na D line, [-]
Notes
-----
Examples
--------
>>> RI_from_molar_refractivity(1.2985e-5, 5.8676E-5)
1.3610932757685672
References
----------
.. [1] Panuganti, Sai R., Fei Wang, Walter G. Chapman, and Francisco M.
Vargas. "A Simple Method for Estimation of Dielectric Constants and
Polarizabilities of Nonpolar and Slightly Polar Hydrocarbons."
International Journal of Thermophysics 37, no. 7 (June 6, 2016): 1-24.
doi:10.1007/s10765-016-2075-8.
'''
Rm = ((-2*Rm - Vm)/(Rm-Vm))**0.5
return Rm
### Mixtures
#def Lorentz_Lorenz(ws=None, RIs=None, rhos=None, rho=None):
# if not length_check([ws, RIs, rhos]):
# raise Exception('Input dimentions are inconsistent')