EN
The spectroscopic studies of anhydrous neodymium perchlorate in two series of 2-halogeno derivatives of ethyl alcohol are presented. The changes of intensities of ^{4}I_{9/2} → ^{2}G_{7/2}, ^{4}G_{5/2} hypersensitive transitions are discussed within the framework of Mason's polarizability mechanism. Anomalous dependence of band intensities was found for the 2-fluoro derivatives. The linear relation of oscillator strength vs. solvent polarizability was broken for the 2-bromine and 2-iodine derivatives of ethyl alcohol. The effort was made for explanation of such strange results.