21. The period of this oscillations depends on the type of the backscattering atom and its distance from the central atom . 22. The " E " represents the number of lone electron " pairs " surrounding the central atom . 23. Interhalogens with five or seven halogens bonded to a central atom are formed by two elements whose sizes are very different. 24. The number of fluorine atoms that are packed around the central atom is an important factor for calculating the bond length. 25. Tetradentate ligands can be neutral, so that the charge of the whole complex is the same as the central atom . 26. In 1940 his Bakerian lecture with Herbert Marcus Powell correlated molecular geometry with the number of valence electrons on a central atom . 27. Interhalogens with one or three halogens bonded to a central atom are formed by two elements whose electronegativities are not far apart. 28. The wavelength of the photoelectron is dependent on the energy and phase of the backscattered wave which exists at the central atom . 29. If it is large it means that potentials on neighboring atoms have a large influence on the energy of the central atom . 30. The ligand can have one bend so that one is at the pole and three on the equator of the central atom .
