I have read that relaxation of a rotational or vibrational mode in gases occurs through collisions of molecules , transferring energy of an excited vibrational mode into heat. But isn't it possible that an excited vibrational mode in molecules relaxes directly by emission of radiation...???? I think that is what happens in thermal radiation heat transfer. According to Wikipedia, "Thermal radiation is the emission of electromagnetic waves from all matter that has a temperature greater than absolute zero. It represents a conversion of thermal energy into electromagnetic energy. Thermal energy results in kinetic energy in the random movements of atoms and molecules in matter. All matter with a temperature by definition is composed of particles which have kinetic energy, and which interact with each other. These atoms and molecules are composed of charged particles, i.e., protons and electrons, and kinetic interactions among matter particles result in charge-acceleration and dipole-oscillation. This results in the electrodynamic generation of coupled electric and magnetic fields, resulting in the emission of photons, radiating energy away from the body through its surface boundary.". So I believe that in case of thermal radiation, some vibrational states directly convert their vibrational energy into electromagnetic energy, without lowering vibrational energy through molecular collisions, and generating heat. Am I correct..????