Property Prediction¶

#!/usr/bin/env amspython
# coding: utf-8

# ## Initial imports

import pyCRS
import matplotlib.pyplot as plt
from rdkit import Chem
from rdkit.Chem.Draw import IPythonConsole
IPythonConsole.ipython_useSVG = True
IPythonConsole.molSize = 150, 150


# ## Property prediction from SMILES (ethyl acetate)

#smiles = 'CCO' # ethanol
smiles = 'O=C(OCC)C' # ethyl acetate
rdkit_mol = Chem.MolFromSmiles(smiles)
rdkit_mol   # show the molecule in a Jupyter notebook


# ### Temperature-independent properties

print(f"SMILES: {smiles}\n")
mol = pyCRS.Input.read_smiles(smiles)

temperatures = [298.15, 308.15, 318.15, 328.15, 338.15]
pyCRS.PropPred.estimate(mol, temperatures=temperatures) 

for prop, value in mol.properties.items():
    unit = pyCRS.PropPred.units[prop]
    print(f'{prop:<20s}: {value:.3f} {unit}')


# ### Temperature-dependent properties (vapor pressure)

prop = 'vaporpressure'
unit = pyCRS.PropPred.units[prop]
temperatures_K, vaporpressures = mol.get_tdep_values(prop)
temperatures_C = [t - 273.15 for t in temperatures_K]  # convert to Celsius

plt.figure(figsize=(3,3))
plt.plot(temperatures_C, vaporpressures)
plt.plot(temperatures_C, vaporpressures, '.')
plt.xlabel("Temperature (degree Celsius)")
plt.title(f'SMILES: {smiles}')
plt.ylabel(f"{prop} [{unit}]");


# ## Create .csv for multiple compounds
# 
# Define a list of compounds by their SMILES strings. This example also shows how to only calculate a subset of all properties.
# 
# Note: The SMILES string 'C' corresponds to methane which is too small to be used with the property prediction tool, so the results are given as 'nan' (not a number).

smiles_list = [
    'CCO', 
    'CCOC', 
    'OCCCN', 
    'C', # methane is too small to be used with property prediction and will return "nan"
    'C1=CC=C(C=C1)COCC2=CC=CC=C2'
]
temperatures = list(range(280,340,10))

mols = [pyCRS.Input.read_smiles(s) for s in smiles_list]

properties = ["boilingpoint", "criticaltemp", "hformstd"]

for mol in mols:
    pyCRS.PropPred.estimate(mol, properties, temperatures=temperatures) 


def get_csv(mols, properties):
    header = "SMILES"
    for prop in properties:
        unit = pyCRS.PropPred.units[prop]
        if unit:
            unit = f' [{unit}]'
        else:
            unit = ''
            
        header += f',{prop}{unit}'
    ret = header + '\n'
    
    for mol in mols:
        s = f'{mol.smiles}'
        for prop in properties:
            value = mol.properties.get(prop, '')
            try:
                s += f',{value:.4f}'
            except TypeError:
                s += f',{value}'
        s += '\n'
        ret += s
    return ret


csv = get_csv(mols, properties)
print(csv)

# To write to a .csv file:
#with open('outputfile.csv', 'w') as f: 
#    f.write(csv)


# ### Bar chart for multiple compounds
# 
# Continuing from the previous example, you can also create e.g. a bar chart with the boiling points:

prop = 'boilingpoint'
values = [mol.properties.get(prop, None) for mol in mols]
plt.barh(smiles_list, values)
plt.title('Boiling point [K]');