QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Inaoton on March 23, 2018, 12:53

Title: How can I build Cubic CH3NH3PbI3
Post by: Inaoton on March 23, 2018, 12:53
Sir
            I have constructed cubic CH3NH3PbI3 using the information provided in the attached pdf file. There is  doubt about the positions of Carbon, Nitrogen and Hydrogen. Could you please check?

# Set up lattice
lattice = SimpleCubic(6.31728*Angstrom)

# Define elements
elements = [Lead, Iodine, Iodine, Iodine, Carbon, Nitrogen, Hydrogen, Hydrogen,
            Hydrogen, Hydrogen, Hydrogen, Hydrogen]

# Define coordinates
fractional_coordinates = [[ 0.            ,  0.            ,  0.            ],
                          [ 0.5           ,  0.            ,  0.            ],
                          [ 0.            ,  0.            ,  0.5           ],
                          [ 0.            ,  0.5           ,  0.            ],
                          [ 0.608982646908,  0.499999999272,  0.499999998033],
                          [ 0.395599671956,  0.499999999724,  0.500000000118],
                          [ 0.334299602243,  0.644802932463,  0.505677910079],
                          [ 0.336439112449,  0.431630966958,  0.371222944337],
                          [ 0.334926288788,  0.422173751157,  0.622554649753],
                          [ 0.668813146403,  0.573960319949,  0.625331593545],
                          [ 0.662871225597,  0.352169718774,  0.500236204806],
                          [ 0.663956675591,  0.571307950288,  0.37096179117 ]]

# Set up configuration
bulk_configuration = BulkConfiguration(
    bravais_lattice=lattice,
    elements=elements,
    fractional_coordinates=fractional_coordinates
    )

Title: Re: How can I build Cubic CH3NH3PbI3
Post by: Inaoton on March 24, 2018, 13:24
In most of the experimental data available, hydrogen positions are not given. Can I add hydrogens by passivation?
Title: Re: How can I build Cubic CH3NH3PbI3
Post by: Petr Khomyakov on March 27, 2018, 12:52
I think you can do it technically indeed, but whether this is a good model for your structure, this can only be checked against some experimental data either for the atomic structure itself or for related physical quantities.