Van der Waals force in quantum physics

In summary, according to QFT, classical physics cannot fully explain quantum effects such as hydrogen bonds and Van der Waals force. These are molecular bonding mechanisms that involve covalent and ionic bonds, as well as electrostatic forces. Van der Waals' forces exist between separate water molecules, while dipole dipole forces occur in polar molecules such as HCl.
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Philipsmett
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According to QFT, are there hydrogen bonds or Van der Waals force? Or this an outdated concept of classical physics?
 
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Those are quantum effects that cannot be explained by classical physics.
 
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I agree Demystifier is correct. I have a little different way of conceptualizing the molecular bonding mechanism. I'll use (H²O) Water to expand my point, (H²) Hydrogen and (O²)Oxygen bind and emerges Water (H²O) molecule(s). The convergent of the water remaining intact is a result of Covalent and Ionic bonds. These molecular bonds are referred to as force(s), -- electrostatic force. This electrostatic force is just the description and name of the 'covalent and ionic bonding' cause but they are NOT van der Waals' forces. The van der Waals' forces are the forces that exist between the millions of separate water molecules, and not between the hydrogen and oxygen atoms in the case of water. Dipole Dipole forces occur in polar molecules, that is, molecules that have an unequal sharing of electrons. To Emphasize - HCl comprised of the atom Hydrogen and Chlorine is polar. The Chlorine atom has an extra electron, which came from the hydrogen atom. Because of this, the chlorine part of the molecule is negatively charged, and the hydrogen side of the molecule is positively charged.
 
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1. What is the Van der Waals force in quantum physics?

The Van der Waals force is a type of intermolecular force that arises due to the interaction between electrically neutral molecules. It is caused by the temporary dipole moments that occur in molecules due to the constant motion of their electrons.

2. How is the Van der Waals force calculated in quantum physics?

In quantum physics, the Van der Waals force is calculated using the London dispersion equation, which takes into account the polarizability of molecules and the distance between them. This equation is based on the quantum mechanical description of electrons and their behavior in molecules.

3. What is the significance of Van der Waals force in quantum physics?

The Van der Waals force is important in understanding the properties of gases, liquids, and solids at the molecular level. It also plays a crucial role in determining the physical and chemical properties of materials, such as their boiling and melting points, viscosity, and surface tension.

4. How does the Van der Waals force differ from other intermolecular forces in quantum physics?

The Van der Waals force is a weaker force compared to other intermolecular forces such as hydrogen bonding or ionic bonding. It is also a non-directional force, meaning it acts equally in all directions, unlike covalent or ionic bonds which have specific directional properties.

5. Can the Van der Waals force be manipulated in quantum physics?

Yes, the Van der Waals force can be manipulated by changing the distance between molecules or by altering the polarizability of the molecules. This can be achieved through various methods such as changing the temperature, pressure, or introducing polarizing agents.

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