Using ab initio conformational energy mapping (HF/3-21G) a maximum of nine characteristic backbone conformation clusters (alpha L, alpha D, beta L, gamma L, gamma D, delta L, delta D, epsilon L, and epsilon D) were previously established for differenr amino acid diamides (e.g., For-L-Ala-NH2, For-L-Val-NH2, and For-L-Phe-NH2). Most of the above nine backbone conformers have been located in the [phi,psi] space for various side-chain conformers. The present conformation analysis derives structural parameters of For-L-Ser-NH2 molecule based on a systematic investigation of the side-chain conformational energy maps {E = E(chi(1),chi(2))} associated with characteristic backbone structures. The systematic mapping of the E E(phi,psi,chi(1),chi(2)) four-dimensional Ramachandran-type map has revealed 44 minima. This finding thus established the complete conformational set for For-L-Ser-NH2. Specific intramolecular hydrogen bonds of the 44 geometry optimized structures were analyzed. These ab initio structures can now be used with greater confidence during force field parameterizations, NMR, and X-ray structure elucidations or even for the characterization of protein backbone structures.