It is hydrophobic (reject water) and non-polar. Its bonds are covalent rather than ionic in character. It has a crystalline polymer structure. In Nafion™ tubing, interspersed throughout this Teflon matrix are sulfonic acid groups. These are hydrophilic (are drawn to water), polar, and ...
The different nature of chemical bonding for Se atoms in these configurations is predominantly ionic, due to GeSe4 tetrahe- dra, or covalent, as arising from Sen chains. This composite scenario called for the use of FPMD as a predictive approach to be preferred to classical molecular dynamics...