31. The model can also be modified to account for mixing of fine structures during the turbulent reaction. 32. Spectral lines of the diffuse series are split into three lines in what is called fine structure . 33. Each electronic transition may show vibrational coarse structure, and for molecules in the gas phase, rotational fine structure . 34. This splitting is called fine structure . 35. The distorted configurations sampled impart their geometrical parameters on, for example, the rotational fine structure in a spectrum. 36. In 1999, evidence for time variability of the fine structure constant based on observation of quasars was announced. 37. Already in 1915, however, Arnold Sommerfeld was able to derive the Fine structure of Bohr Sommerfeld theory ). 38. The value of those wavelengths, in turn, is directly related to the value of the fine structure constant. 39. This preserves a greater degree of fine structure with the ultrastructural details marked by small particles of gold. 40. Vibrational bands have rotational fine structure .