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As first pointed out by $Condon,h$ a strong electric field can induce new features in the infrared spectra of molecules, which will follow the Raman selection rules. Following our observation of the pure vibrational $Q1(0)$ transition induced by the electric field of ionic species in solid parahydrogen a new modulation technique with much improved sensitivity based on the Condon effect has been $established.i$ Using this technique, we have systematically studied the linewidth frequency shift, and lineshape of the pure vibrational Transitions of samples of parahydrogen crystals (with less than 0.07% of orthohydrogen) at various temperature. Results from this work provide information on the relaxation process in this system, which will lead to a better understanding of the origin of the sharpness of the transitions in solid hydrogens. In this paper, the analysis of our results will be presented.