The experimentally observed hemi-directed coordination mode in 1D polymeric Pb2+ ferrocenylcarboxylate system is examined computationally for gaining better insights on the structure of polymeric systems. By considering the different size of the ligands such as methylcarboxylate (model system) and ferrocenylcarboxylates (real system), the coordination mode is systematically explored in the complexes 1–6. As expected due to the possibility of free rotation in the methylcarboxylate systems in solution, it may follow holo-directed geometrical arrangements but interestingly, it shows only hemi-directed geometry as observed in the experimental studies on ferrocenylcarboxylate system (N. Palanisami et al. Science of Advanced Materials, 2014, 6, 2364). The present computational studies predict that the lone pair electrons in Pb2+ play the dictating role for formation of hemi-directed coordination mode in methylcarboxylates as well as in ferrocenylcarboxylates. The directionality of the lone pair electrons makes the remarkable differences in the structural arrangements. Notable difference observed is that the methylcarboxylate shows the linear fashion of hemi-directed coordination whereas ferrocenylcarboxylate shows the zig-zag fashion of hemi-directed coordination. The quantitative and qualitative characteristics of lone pair electrons in reported systems are assessed through NBO analysis thus it shows the s-LP character occupancy in each case varies from 96% to 93% which is the strong evidence for the availability of lone pair electrons in Pb2+ carboxylate systems. Further, frontier molecular orbital analysis, vibrational modes and hydrogen bonding pattern are explored in the complexes 1–6. © 2020 John Wiley & Sons, Ltd.