Electron transmission spectroscopy is employed to observe the temporary negative ion states of HCN, CH3CN, CH2(CN)2, acrylonitrile, fumaronitrile, tetracyanoethylene (TCNE), benzonitrile, and tetracyanoquinodimethane (TCNQ). The majority of the observed anion states are assigned by means of molecular orbital (MO) calculations. Stabilization calculations are carried out for fumaronitrile and TCNE and provide an important calibration of the MO calculations without stabilization.