The compounds [Cu(pmda)(crea)]·H2O (1), [Zn(pmda)(crea)]·H2O (2) and [Co(pmda)(crea)(H2O)]·H2O (3) were prepared and characterized by thermal, spectral and X-ray diffraction methods. In compounds 1 and 2 the MII coordination is of type 4+1 and approaches to a trigonal bipyramid (71.85 and 86.18 %, respectively) with rather linear N(pmda)-MII-N(crea) trans-apical angles, but with different longest coordination bond (Cu-O(pmda) or Zn-N(apliphatic, pmda), respectively). Both compounds are isotypic and one intra-molecular interligand N-H···O interaction reinforces the molecular recogniton crea-MII(pmda) chelate. In contrast, the compound 3 exhibits an octahedral coordination, imposed by the 3d7 electronic configuration of the cobalt(II) atom, and the crea-chelate recognition involves the Co-N(crea) coordination bond and one intramolecular ‘bifurcated’ H-bonding interaction between one N-H(crea) bond and one O(pmda) plus the O(aqua) atoms as ‘acceptors’.