SELEKTIVITAS ETER MAHKOTA TERHADAP KATION LOGAM, PEMODELAN MOLEKUL BERDASARKAN METODE AB INITIO
| Main Authors: | , Yahmin, , Prof. Dr.rer.nat. Harno Dwi Pranowo, M.Si. |
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| Format: | Thesis NonPeerReviewed |
| Terbitan: |
[Yogyakarta] : Universitas Gadjah Mada
, 2012
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| Subjects: | |
| Online Access: |
https://repository.ugm.ac.id/100557/ http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=57009 |
Daftar Isi:
- Selectivity of 12C4, 15C5, DBz12C4 and DBz15C5 to bind some metal cations Mn+, (Mn+ = Li+, Na+, K+, Zn2+, Cd2+ and Hg2+), were studied based on an ab initio Hartree-Fock method using LanL2MB as a basis set. The effects of microsolvation and the substituent effects of -CH3, -OCH3, -CH=CH2, - CH(OH)CH3, -CHO, -COOH, -Cl and -Br on the selectivity of crown ethers were studied. Geometry optimization, vibration frequency and energy interaction calculation have been done to the structure of crown ethers, crown ether-cation complexes, and crown ether-cation complexes in the microsolvation system. Selectivity of crown ethers were discussed in term of the structure parameter of crown ethers, interaction energies, IR spectra of the complexes, thermodynamics properties and atomic charges. The result showed that selectivity of crown ethers to bind metal cations follows the sequence order of Li+> Na+ > K+ and Zn2+ > Cd2+ > Hg2+. Substituents containing electron donating groups, -CH3, -OCH3, -CH=CH2 and -CH(OH)CH3 increase selectivity of crown ethers in cations binding by induction effect, while electron withdrawing groups, -CHO, -COOH, -Cl and Br, reduce the ability of crown ethers to bind cations. Microsolvation by addition of one water molecule increase the stability of [Mn+.12C4] and [Mn+.DBz12C4] complexes. The addition of two water molecules on [Mn+.15C5] and [Mn+.DBz15C5] complexes stabilized conformation of the complexes by maintaining the cations inside the cavity of crown ethers, except for K+ cation. Frequency of vibration and thermodynamics properties show that all complexes under consideration are stable complexes.