Table 2. Mol % of Metal Incorporated into the Bulk (Measured with Elemental Analysis) and Surfaces (Measured with XPS) of α-Gly Crystals Grown in the Presence of 1 mol % of Metal Salt from Aqueous Solutions at S between 1.3 and 1.45.

metal ion	mol % of metal in bulk (%)	mol % of metal in {011} (%)	mol % of metal in {020} (%)
Fe(II)	0.27	12	0a
Cu(II)	0.14	5	0a
Zn(II)	<0.1a	2	0a

^aBelow detection limit.