Understanding the Rule of Delta E = A/r^12 - B/r^6 in Physics Crystallography

Thread starter Amr Reda
Start date Aug 15, 2014
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Crystallography Physics

In summary, the "Delta E" in the rule of Delta E = A/r^12 - B/r^6 refers to the difference in energy between two particles or atoms, indicating the strength of their interaction. The A/r^12 term represents attractive forces and the B/r^6 term represents repulsive forces, with the exponents 12 and 6 representing the strength of these forces. This rule is specific to interactions between neutral particles and is used in crystallography to calculate potential energy and understand the structure and properties of crystals.

Aug 15, 2014

Amr Reda

what is the rule of delta E= A/r^12 _ B/r^6 ?

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Aug 16, 2014

Vagn

Amr Reda said:

what is the rule of delta E= A/r^12 _ B/r^6 ?

That would appear to be the simple form of the Lennard-Jones potential.

1. What is the significance of the "Delta E" in the rule of Delta E = A/r^12 - B/r^6?

The "Delta E" in this rule refers to the difference in energy between two particles or atoms. It is a measure of the strength of the interaction between the particles, with a larger Delta E indicating a stronger attraction between them.

2. How does the "A/r^12 - B/r^6" term in the rule relate to the attractive and repulsive forces between particles?

The A/r^12 term represents the attractive forces between particles, while the B/r^6 term represents the repulsive forces. As the distance between particles decreases, the attractive forces dominate and the energy decreases, while at very close distances the repulsive forces become dominant and the energy increases.

3. What is the significance of the exponents 12 and 6 in the rule of Delta E = A/r^12 - B/r^6?

The exponents 12 and 6 in this rule represent the strength of the attractive and repulsive forces, respectively. The larger the exponent, the stronger the force. This is due to the fact that the potential energy of the interaction between particles decreases exponentially as the distance between them decreases.

4. Can the rule of Delta E = A/r^12 - B/r^6 be applied to all types of interactions between particles?

No, this rule is specifically applicable to interactions between neutral particles, such as atoms and molecules. It does not apply to interactions involving charged particles, which follow different rules and equations.

5. How is the rule of Delta E = A/r^12 - B/r^6 used in crystallography?

In crystallography, this rule is used to calculate the potential energy of interactions between atoms in a crystal lattice. By understanding the strength of these interactions, scientists can better understand the structure and properties of crystals, which is important in fields such as material science and chemistry.