Magnetic interactions and aromatic ring stacking: an EPR study with the two systems dichlorobis and dibromobis-1-phenyl-3-5-dimethylpyrazole - Nascimento, Otaciro Rangel; Costa Filho, Antonio José da; Munte, Cláudia Elisabeth; Mattioli, Pedrini; Calvo, Rafael (Rocky Mountain Conference on Analytical Chemistry, 1996)