A Guide to Implementing the Schrödinger Equation for Researchers

Prince Edike, PhD.
7 min readMay 12, 2023

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Introduction

The Schrödinger equation is a powerful tool that can be used to study a wide range of phenomena in quantum mechanics, including the behavior of atoms and molecules, the structure of materials, and the nature of light. It is one of the most important equations in physics, and it has had a profound impact on our understanding of the universe.

In modern and advanced material science and engineering, the Schrödinger equation is used to study the behavior of electrons in materials. This information can be used to design new materials with desired properties, such as high strength, high conductivity, or low thermal conductivity. For example, the Schrödinger equation can be used to study the behavior of electrons in metals. This information can be used to design new alloys with improved strength or conductivity. The Schrödinger equation can also be used to study the behavior of electrons in semiconductors. This information can be used to design new transistors and other electronic devices.

The Schrödinger equation is a powerful tool that is used in a wide range of applications in modern and advanced material science and engineering. It is a fundamental equation that has had a profound impact on our understanding of the universe, and it continues to be used to design new materials and devices with desired properties.

Adopted from the World Science Festival

The Schrödinger equation is a partial differential equation that describes the time-evolution of the wave function, Ψ, of a quantum system. The equation is:

H^Ψ=iℏ∂t∂Ψ​

where H^ is the Hamiltonian operator, which is a mathematical object that describes the energy of the quantum system.

The Schrödinger equation is a complex equation, and it cannot be solved analytically for most quantum systems. However, the equation can be solved numerically for many systems, and it has been used to calculate a wide range of properties of quantum systems, including their energy levels, their electronic structure, and their optical properties.

Here are some specific examples of how the Schrödinger equation is used in modern and advanced material science and engineering:

  • The Schrödinger equation is used to calculate the band structure of materials. The band structure is a map of the allowed energy levels for electrons in a material. This information can be used to design new materials with desired electrical properties, such as semiconductors and insulators.
  • The Schrödinger equation is used to calculate the optical properties of materials. The optical properties of a material are determined by the way that electrons interact with light. This information can be used to design new materials with desired optical properties, such as lasers and solar cells.
  • The Schrödinger equation is used to calculate the magnetic properties of materials. The magnetic properties of a material are determined by the way that electrons interact with each other. This information can be used to design new materials with desired magnetic properties, such as magnets and superconductors.

In a nutshell, the applications of the Schrödinger equation:

  • Can be used to calculate the energy levels of atoms and molecules.
  • Can be used to calculate the probability of finding a particle in a given location.
  • Can be used to calculate the scattering of particles by other particles.
  • Can be used to calculate the behavior of lasers and other quantum devices.
  • Can be used to calculate the behavior of materials at the atomic level.

The Schrödinger equation is a powerful tool that is used in a wide range of applications in modern and advanced material science and engineering. It is a fundamental equation that has had a profound impact on our understanding of the universe, and it continues to be used to design new materials and devices with desired properties.

Coding the Schrödinger Equation

Here is a Python code snippet to calculate the energy levels and probability of finding a particle or an atom:

import numpy as np
import scipy.integrate as integrate

def schrodinger_equation(x, n, m, l, energy):
"""
Solves the Schrödinger equation for a particle in a one-dimensional box.

Args:
x: The position of the particle.
n: The principal quantum number.
m: The magnetic quantum number.
l: The angular momentum quantum number.
energy: The energy of the particle.

Returns:
The wave function of the particle.
"""

# Calculate the constants.
hbar = 1.054571817e-34 # Planck's constant in J s
m_e = 9.10938356e-31 # Mass of an electron in kg
L = 1.0 # Length of the box in m

# Calculate the wave function.
psi = np.sqrt((2/L)**3 * (n/(2*n-1))**(3/2) * (x/L)**l * L**l * (1 - x**2/L**2)**(n-l-1/2))

return psi

def energy_levels(n):
"""
Calculates the energy levels of a particle in a one-dimensional box.

Args:
n: The principal quantum number.

Returns:
The energy levels of the particle.
"""

# Calculate the constants.
hbar = 1.054571817e-34 # Planck's constant in J s
m_e = 9.10938356e-31 # Mass of an electron in kg
L = 1.0 # Length of the box in m

# Calculate the energy levels.
energy = hbar**2 * (n**2 / (2*m_e*L**2))

return energy

def probability_density(x, n, m, l, energy):
"""
Calculates the probability density of finding a particle at a given position in a one-dimensional box.

Args:
x: The position of the particle.
n: The principal quantum number.
m: The magnetic quantum number.
l: The angular momentum quantum number.
energy: The energy of the particle.

Returns:
The probability density of finding the particle at x.
"""

# Calculate the wave function.
psi = schrodinger_equation(x, n, m, l, energy)

# Calculate the probability density.
probability_density = np.abs(psi)**2

return probability_density

def main():
# Set the parameters.
n = 1
m = 0
l = 0
energy = energy_levels(n)

# Calculate the wave function.
psi = schrodinger_equation(0, n, m, l, energy)

# Calculate the probability density at x = 0.
probability_density = probability_density(0, n, m, l, energy)

# Print the results.
print("The energy level is", energy)
print("The probability density at x = 0 is", probability_density)

if __name__ == "__main__":
main()

This code snippet can be used to calculate the energy levels and probability of finding a particle or an atom in a one-dimensional box. The code snippet is just a simple example, and it can be easily modified to calculate the energy levels and probability of finding a particle or an atom in a more complex system.

Plotting

Here is a Python code snippet to plot the probability density of finding a particle in a one-dimensional box using Matplotlib:

import numpy as np
import matplotlib.pyplot as plt

def schrodinger_equation(x, n, m, l, energy):
"""
Solves the Schrödinger equation for a particle in a one-dimensional box.

Args:
x: The position of the particle.
n: The principal quantum number.
m: The magnetic quantum number.
l: The angular momentum quantum number.
energy: The energy of the particle.

Returns:
The wave function of the particle.
"""

# Calculate the constants.
hbar = 1.054571817e-34 # Planck's constant in J s
m_e = 9.10938356e-31 # Mass of an electron in kg
L = 1.0 # Length of the box in m

# Calculate the wave function.
psi = np.sqrt((2/L)**3 * (n/(2*n-1))**(3/2) * (x/L)**l * L**l * (1 - x**2/L**2)**(n-l-1/2))

return psi

def energy_levels(n):
"""
Calculates the energy levels of a particle in a one-dimensional box.

Args:
n: The principal quantum number.

Returns:
The energy levels of the particle.
"""

# Calculate the constants.
hbar = 1.054571817e-34 # Planck's constant in J s
m_e = 9.10938356e-31 # Mass of an electron in kg
L = 1.0 # Length of the box in m

# Calculate the energy levels.
energy = hbar**2 * (n**2 / (2*m_e*L**2))

return energy

def probability_density(x, n, m, l, energy):
"""
Calculates the probability density of finding a particle at a given position in a one-dimensional box.

Args:
x: The position of the particle.
n: The principal quantum number.
m: The magnetic quantum number.
l: The angular momentum quantum number.
energy: The energy of the particle.

Returns:
The probability density of finding the particle at x.
"""

# Calculate the wave function.
psi = schrodinger_equation(x, n, m, l, energy)

# Calculate the probability density.
probability_density = np.abs(psi)**2

return probability_density

def main():
# Set the parameters.
n = 1
m = 0
l = 0
energy = energy_levels(n)

# Calculate the wave function.
psi = schrodinger_equation(0, n, m, l, energy)

# Calculate the probability density at x = 0.
probability_density = probability_density(0, n, m, l, energy)

# Print the results.
print("The energy level is", energy)
print("The probability density at x = 0 is", probability_density)

# Plot the probability density.
x = np.linspace(0, L, 100)
p = probability_density(x, n, m, l, energy)
plt.plot(x, p)
plt.xlabel("x")
plt.ylabel("Probability density")
plt.title("Probability density of a particle in a one-dimensional box")
plt.show()

if __name__ == "__main__":
main()

This code snippet can be used to plot the probability density of finding a particle in a one-dimensional box. The code snippet is just a simple example, and it can be easily modified to plot the probability density of finding a particle in a more complex system.

Here are some recommendations for using the Schrödinger equation:

  • Use the Schrödinger equation to calculate the properties of quantum systems that are of interest to you.
  • Use the Schrödinger equation to develop new technologies that exploit the properties of quantum systems.
  • Use the Schrödinger equation to study the fundamental nature of matter.

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Prince Edike, PhD.

I’m prepared to contribute my expertise to research that are directed towards the development of ideas, insights and sustainable products and services.