Physics of Advanced Materials Winter School 2008 1 The Röntgen Radiation and its application in studies of advanced materials written by Mihaela Alexandru “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania,aleaahim@yahoo.com and Alexandra Nistor “Gh. Asachi” Technical University Iasi, Romania, anistor@ch.tuiasi.ro based on the lecture of Prof. Tomasz Goryczka University of Silesia, Poland, goryczka@us.edu.pl Abstract The wave-particle dual nature of the electromagnetic radiation was emphasized through the discovery of X-rays. The X-rays are, posses the same nature as light has, electromagnetic waves, but in comparison to the light rays, the X radiation has a much higher frequency. According to Planck’s formula, the energy of X photon is correspondingly higher. It explains why properties of the X radiations manifest more evidently in comparison to those of the light. On this occasion another important particle-like property of the photon will be highlighted and that is the impulse. 1. Introduction On November 8th 1890, Professor Wilhelm Conrad Röntgen (1845-1923) was working alone in his room from the Physics Laboratory of the Wurzburg University, as always. Although he was in his fifties at the time and he had by then published numerous articles. Röntgen decided to approach a new field of science – the field of gas electrical discharges. In order to study fluorescence phenomena, he carried out experiments in a Crooke’s tube using an electrical discharge obtained form an induction coil. Röntgen covered the tube with a black cardboard to increase luminescence phenomena. By chance, besides the Crookes tube, there was a screen covered with barium platinocyanide. Röntgen was amazed seeing the Crookes tube, which was under tension, and the screen mysteriously became fluorescent, although nothing seemed to fall on it. The property of the barium platinocyanide as a fluorescent material was well-known. Despite, the fluorescence phenomena there were other kinds of radiation, which made negatives stacked in a laboratory’s corner completely dark. He realized that it must have been new radiation. From that, the rays became known as a Roentgen radiation. Röntgen studied its properties and found a lot of practical applications. One of them is possibility to be absorbed at different rates by the soft tissues and bones [1]. On this occasion, Röntgen made the first radiography that represents the left hand of his wife.