Pemodelan Molekul Kompleks Mn+.[DBz16C5], M = Li+, Na+ dan Zn2+ dengan Metode Semiempirik MNDO/d
ABSTRACT: The effect of
substituent on dibenzo-16-crown-5 (DBz16C5) and interaction between these crown
ether with metal cations was evaluated using computational chemistry
calculations. Substituens where are connected to the benzene ring on the
DBz16C5 are -COOH, -Br, -COOC2H5, -CHO, -CH=CHCO2H, -CH=CHCO2C2H5 and
-CH(OH)CH3. The analysis based on computational chemistry calculation using
MNDO/d semi empirical method was done. The first step is structure optimization
of crown ether followed by optimization of crown ether-metals cation complexes
Mn+.[DBz16C5], where M is Li+, Na+ and Zn2+. Interactions of the crown ether
and cation were discussed in term of the structure parameter of crown ether,
atomic charges and energy interaction of the crown ether-metals cation. Electron
donating groups increase the capability of crown ether to bind cation by means
of induction effect, while electron withdrawing groups reduce the ability of
crown ether to bind cation. Any substituent on the benzene in DBz16C5 which can
be make the symmetrical form of the crown ether-metals cation complexes will
increase the selectivity of the crown ether to bind the cation. Selectivity of
the crown ether to bind cation also depends on the compatibility of the
diameter of cation and cavity of crown ether. DBz16C5 has higher selectivity to
bind the Na+ compare to the Li+ and Zn2+.
Penulis: Harno Dwi Pranowo,
Chairil Anwar
Kode Jurnal: jpkimiadd060064
