Molecular cups and capsules through hydrogen bonding

Organization of the interior of molecular capsules by hydrogen bonding.

The enclosure of functional entities within a protective boundary is an essential feature of biological systems. On a molecular scale, free-standing capsules with an internal volume sufficiently large to house molecular species have been synthesized and studied for more than a decade. These capsules have been prepared by either covalent synthesis or self-assembly, and the internal volumes have ...

Spin Transfer through Hydrogen Bonding

A polarised-neutron diffraction experiment on [Co(NH3)5(H20)][Cr(CN)6] shows the unexpected features of spin populat ions on the cobalt ((0.5(2) e) and the "ammine" hydrogen (0.8(1) e in total) atoms. A local density approximation DV-Xa calculation on a unit that models the molecular geometry in the crystal returns features that are broadly in agreement with the experiment. The calculation also...

Halogen Bonding versus Hydrogen Bonding: A Molecular Orbital Perspective

We have carried out extensive computational analyses of the structure and bonding mechanism in trihalides DX⋅⋅⋅A(-) and the analogous hydrogen-bonded complexes DH⋅⋅⋅A(-) (D, X, A=F, Cl, Br, I) using relativistic density functional theory (DFT) at zeroth-order regular approximation ZORA-BP86/TZ2P. One purpose was to obtain a set of consistent data from which reliable trends in structure and stab...

Halogen Bonding versus Hydrogen Bonding: A Molecular Orbital Perspective Previously appeared as Halogen Bonding versus Hydrogen Bonding: A Molecular Orbital Perspective

Hydrogen bonding

molecules to evolve in the test tube. With the discovery of catalytic RNA, and advances in nucleic acid amplification techniques such as the polymerase chain reaction, it became possible to construct laboratory systems that allow the Darwinian evolution of functional RNA (and later DNA) molecules. This is not evolution based on natural selection, but rather directed evolution based on selection...