Atomization of Cu, Ag, Ni and In at constant temperature from tungsten probe surface

The kinetic order and activation energy of Cu, Ag, Ni and In for atom formation under isothermal condition in a graphite furnace have been determined by means of a newly developed method. A 2/3 order kinetic release of Cu indicates that the analyte desorbs from the surface of microdroplets on the probe with desorption energy of 193 +/- 24 kJ mol(-1). For Ag and In a fractional order of near 1/2 with E(a) values of 248 +/- 5 kJ mol(-1) and 123 +/- 8 kJ mol(-1), respectively, was obtained which implies the release of free Ag or In atoms from the interface of 2-D islands. As to Ni, a first-order kinetic process was observed with E(a) value of 297 +/- 6 kJ mol(-1), which suggests that the analyte desorbs from tungsten probe surface as highly dispersed atoms. The activation energy may represent the nickel-tungsten interaction energy.