<i>Ab Initio</i> Study of Proton Transfer and Hydration in Phosphorylated Nata de Coco

Abstract

This research aims to calculate energetics parameters, hydrogen bonding, characteristics local hydration, and proton transfer in phosphorylated nata de coco (NDCF) membrane using ab initio method. The minimum energy structure of NDCF membranes and the addition of n water molecules (n = 1-10) Calculation of the rotational energy at the center of C-O indicates that the pyranose ring structure, with a maximum barrier energies of~12.5 J/mol, is much more flexible than the aromatic backbones of sulfonated poly(phenylene) sulfone (sPSO2) and the polytetrafluoroethylene (PTFE) backbones in perfluorosulfonic acid ionomers (PFSA). These energy calculations provide the basis that the flexibility of the pyranose ring and the hydrogen bonding between water molecules and phosphonate groups influence the transfer of protons in the membrane of NDCF. Keywords: proton transfer; ab initio; nata de coco ABSTRAK Penelitian ini bertujuan untuk menghitung parameter energetika, ikatan hidrogen, karakteristik hidrasi lokal, dan transfer proton pada membran nata de coco terfosfosfatasi menggunakan metode ab initio. Struktur energi minimum untuk nata de coco terfosfatasi dan penambahan n molekul air (n = 1-10) yang ditentukan dengan metode B3LYP/6-311G(d) menunjukkan bahwa untuk disosiasi proton minimal dibutuhkan empat molekul air. Proton yang terdisosiasi distabilkan dengan terbentuknya ion-ion hidronium, Zundel dan Eigen. Perhitungan energi interaksi dengan n molekul air menunjukkan perubahan energi (∆E), dan perubahan entalpi (∆H) yang semakin negatif. Hal ini

Quantum Chemical Calculation for Intermolecular Interactions of Alginate Dimer-Water Molecules

“…Dissociation of alginic acid molecules happened as the water molecule number increased, which was presented with the longer bond lengths of O7-H39 and O11-H43, which were up to 1 Å. The same results were also reported by previous researchers [ 41 , 42 ]. On the other hand, Table 2 showed that sodium’s hydration process of carboxylic sodium salt occurred in addition to two water molecules, which was proved by the fact that the distance between O and Na was longer than 2.3 Å.…”

Revealing the incorporation of an NH2group into the edge of carbon dots for H2O2sensingviathe C–N⋯H hydrogen bond interaction

“…The adsorption energy values classified the interaction as a medium hydrogen bond interaction because they were in the range of −4 kcal mol −1 < adsorption energies < −20 kcal mol −1 . 66,67 Secondly, the adsorption distance of the complex molecules was calculated by the distance between the N atom (in the NH 2 -Cdots) and the H atom from H 2 O 2 . The adsorption distance of the complex molecules in the C–N⋯H hydrogen bond interaction of 1-com is smaller than that of 2-com and 3-com.…”

“…All adsorption distances were in the range of 1.5 Å < adsorption distances < 2.2 Å, and classified the interaction as a medium hydrogen bond interaction. 66,67 Finally, the Mulliken atomic charges 68 of H 2 O 2 before and after adsorption were used to measure the charge transfer of H 2 O 2 molecules adsorbed on the NH 2 -Cdots; a negative Q t value suggests electron accumulation of the H 2 O 2 . 69,70 The charge transfer was highest for 1-com compared with 2-com and 3-com.…”

“…All adsorption distances were in the range of 1.5 Å o adsorption distances o 2.2 Å, and classified the interaction as a medium hydrogen bond interaction. 66,67 Finally, the Mulliken atomic charges 68 of H 2 O 2 before and after 69,70 The charge transfer was highest for 1-com compared with 2-com and 3-com. Therefore, 1-com is the most stable complex molecule.…”

Hydration and Proton Transfer Processes in Sulfonated Nata De Coco Membrane with Density Functional Theory

“…Furthermore, the analysis of proton transfer through the interaction of NDCS with n H2O, which is by adding n water molecules (n = 1,2, ... 10) gradually to the NDCS membrane into the representative structural model. The method used is the DFT method with functional B3LYP and 6-311G (d) basis set and then corrected for zero point energy (ZPE) and BSSE as has been done by Wang and Paddison on sulfonated poly phenylene and Rahmawati et al on NDCP [9,15]. This is done to determine the characteristics of hydration, dissociation and transfer of protons in the membrane.…”