Electron spin echo signals from a powder sample of Cu(II)-(alkylthio)tetraazaporphrin diluted in the corresponding Ni(II) compound are analyzed. The electron spin echo envelope modulation is analyzed to determine the structural arrangement around the paramagnetic center, and the electron spin echo decay is studied to obtain information on the electron spin relaxation mechanism. This information is of help in elucidating the structure and properties of LangmuirBlodgett films fabricated by the title material. The experiments were run both at X-band (9.8 GHz) and at S-band (2.7 GHz), and the experimental spectra were interpreted by best-fit procedures with computed patterns in the time domain.