Addendum: I just learned that dipole-dipole interaction are classified as a type of vdW force in chemistry. This is different from solid state physics, where vdW is reserved for the quantum mechanical effect of induced dipole—induced dipole interaction.
So it’s indeed vdW forces that keep a protein in its shape. (This might also explain why OP found different oom for their strength?)
Addendum: I just learned that dipole-dipole interaction are classified as a type of vdW force in chemistry. This is different from solid state physics, where vdW is reserved for the quantum mechanical effect of induced dipole—induced dipole interaction.
So it’s indeed vdW forces that keep a protein in its shape. (This might also explain why OP found different oom for their strength?)