For an intermolecular attraction, there should be a charge separation. This is also known as London dispersion forces. This is known as dipole dipole interaction. When the positive end of one molecule and the negative end of another molecule are close by, an electrostatic interaction will form between the two molecules.

The atom with a higher electronegativity gets the slight negative charge, and the atom with a lower electronegativity will get the slight positive charge. At this instance, we say that the atoms have obtained a partial negative or positive charge (dipole). Because of the uneven sharing of electrons, one atom will have a slightly negative charge whereas the other atom will have a slightly positive charge. This will result in an unequal distribution of electrons between the two atoms. Therefore, the bond electron pair is pulled more by one atom compared to the other atom, which is participating in making the bond. When the two atoms that form a bond are different, their electronegativities are often different. Down the group, the electronegativity values decrease. Therefore, halogens have larger electronegativity values in a period, and group 1 elements have comparatively low electronegativity values. From left to right through a period, the electronegativity value increases. Fluorine has the highest electronegativity value, which is 4 according to the Pauling scale. In the periodic table, there is a pattern as to how the electronegativity values are changing. Usually Pauling scale is used to indicate the electronegativity values. Electronegativity gives a measurement of an atom to attract electrons in a bond. Polarity arises due to the differences in electronegativity.

These bonds determine the behavior of molecules. However, all of these intermolecular interactions are weaker than the intramolecular forces like covalent or ionic bonds. Some intermolecular forces are strong while some are weak. The primary issue with your intuition is merely understanding what cooling the substance down really does.Dipole Dipole vs Dispersion |В Dipole Dipole Interactions vs Dispersion ForcesДipole dipole interactions and dispersion forces are intermolecular attractions between molecules. As the cooling continues, the molecules move around less and less until they take on a definite shape, at which point it is considered a solid. If the substance is cooled far enough, those forces are able to overcome the kinetic energy of the molecules and they condense into a liquid. But, as the molecules are cooled and slowed down ( this seems to suggest this is around 10m/s), London forces can cause more interactions between molecules. At those speeds, London forces don't really have much of an effect. While in the gaseous phase, the molecules have velocities of several hundred meters per second. At this point, it's not that the dispersion forces because stronger, but rather that they become comparatively stronger.

So, the substance has been cooled down and molecules are moving more slowly. As mentioned in the comments on the question, this doesn't really affect the electron cloud. When we lower the temperature of a substance, we are decreasing the average molecular kinetic energy (they're slowing down). This is how I thought of it, can anyone suggest what's wrong with my way of thinking of it? Is it that what we relate to the strength of the London forces is how long the electrons cloud stay on one side rather than how often that happens? we decrease the frequency/probability of these 'electron clouds' moving to one side of the molecule and forming instantaneous and induced dipole, which means that London forces should be weaker and not stronger to form a liquid or a solid. My question is: if we lower the temperature we subsequently decrease the kinetic energy of the electrons, i.e. The aforementioned statement suggests that as we lower the temperature we form a solid or a liquid meaning that the inter-molecular forces (London forces in this case)became stronger._ I learned that what results in London fores between molecules is the 'cloud of electrons' that results in an instantaneous dipole and induced dipole, which eventually results into forming these weak London forces._ 'London (dispersion) forces are responsible for the fact that non-polar substances can be condensed to form liquids and sometimes solids at low temperatures'._