Physics & Astronomy ETDs

Publication Date



A nucleus with an asymmetric charge distribution (an asymmetric arrangement of protons) exhibits a quadrupole moment which interacts with the gradient of the electric field of the surrounding electrons. The interaction energy is a function of the angle between the nuclear spin axis and the axis of the surrounding electric field. The nucleus processes about the electric field axis in quantized energy states. These quantized energy states correspond to a hyperfine splitting simi­lar to the hyperfine structure of the magnetic dipole-dipole interaction between the nucleus and the electrons. The application of an external electric field, oscillating at the processional frequency of the nucleus, can cause the nucleus to be stimulated into a higher, quantized energy level. When the electric field is turned off, or the frequency of oscillation is changed, the nucleus makes a transition back to the lower energy level. The relaxation time is a measure of the time it takes the nucleus to make this transition after the field has been turned off. Knowledge of this relaxation time can yield information concerning the nature and frequency of molecular and lattice motions in the solid phase. The purpose of this experimental investigation was to determine this relaxation time for the c135 nucleus in a sample of 2,4-dichlorophenoxy­acetic acid (2,4-D).

Degree Name


Level of Degree


Department Name

Physics & Astronomy

First Committee Member (Chair)

Christopher Dean

Second Committee Member

Colston Chandler

Third Committee Member

Seymour Samuel Alpert

Fourth Committee Member

Christopher Pratt Leavitt



Document Type