Measurements of 3d occupancy from Cu L2,3 electron-energy-loss spectra of rapidly quenched CuZr, CuTi, CuPd, CuPt, and CuAu.

We used electron-energy-loss spectrometry to measure the intensities of the Cu white lines found at the onsets of the [ital L][sub 2] and [ital L][sub 3] absorption edges of rapidly quenched CuZr, CuTi, CuPd, CuPt, and CuAu. Enhancements of the white lines in the alloys as compared to elemental Cu were correlated with changes in the 3[ital d] occupancy of Cu atoms upon alloying. We found that the Cu atoms lost 0.2[plus minus]0.06 [ital d] electrons when alloyed with Ti or Zr, 0.0[sub [minus]0.0][sup +0.06] [ital d] electrons when alloyed with Au or Pd, and 0.03[sub [minus]0.03][sup +0.06][ital d] electrons when alloyed with Pt. We found no strong correlation between measured 3[ital d]- occupancy changes and heats of formation of the alloys, consistent with expectations that outer [ital s] electrons play an important role in the alloying of Cu with Pt, Pd, and Au.