New methods for determining chemical structures from residual dipolar couplings are presented. The fundamental dipolar coupling equation is converted to an elliptical equation in the principal alignment frame. This elliptical equation is then combined with other angular or dipolar coupling constraints to form simple polynomial equations that define discrete solutions for the unit vector(s). The...

Recently Groh and Dietrich[1] calculated orientational order transitions for dipolar fluids contained in spheroidal shapes of aspect ratio k. According to their study the thermodynamic state of a dipolar fluid depends on the shape of the fluid's container. For example, a homogeneous fluid in a short fat container would phase separate when transferred to a tall skinny container of identical volu...

Residual dipolar couplings provide significant structural information for proteins in the solution state, which makes them attractive for the rapid determination of protein folds. Unfortunately, dipolar couplings contain inherent structural ambiguities which make them difficult to use in the absence of additional information. In this paper, we describe an approach to the construction of protein...

Aquaporins (AQPs) feature highly selective water transport through cell membranes, where the dipolar orientation of structured water wires spanning the AQP pore is of considerable importance for the selective translocation of water over ions. We recently discovered that water permeability through artificial water channels formed by stacked imidazole I-quartet superstructures increases when the ...

Common cases of cycloaddition include concerted (2 + 4) and stepwise (2 + 2) reactions which latter are usually easily recognizable as involving biradicals or dipolar ions. The addition in situ of dichioroketene to 2,4-hexadiene and 2butene is stereospecific, as required by the (2 + 2a) mechanism, but is followed by rapid base-catalysed rearrangement of the resulting 2,2-dichiorocyclobutanones ...

Dynamic dipolar interactions between spin wave eigenmodes of closely spaced nanomagnets determine the collective behavior of magnonic and spintronic metamaterials and devices. However, dynamic dipolar interactions are difficult to quantify since their effects must be disentangled from those of static dipolar interactions and variations in the shape, size, and magnetic properties of the nanomagn...

A simple and effective method is described for simultaneously measuring dipolar couplings for methine, methylene, and methyl groups in weakly oriented macromolecules. The method is a J-modulated 3D version of the well-known [1H-13C] CT-HSQC experiment, from which the J and dipolar information are most accurately extracted by using time-domain fitting in the third, constant-time dimension. For C...

Quantum-information processing is carried out using dipolar coupled spins and high-resolution nuclear magnetic resonance ~NMR!. The systems chosen are the dipolar coupled methyl protons of CH3CN partially oriented in a liquid crystalline matrix yielding a two-qubit system and dipolar coupled C and methyl protons of CH3CN also partially oriented in the liquid crystalline matrix, yielding a three...

the catalytic highly regio-, diastereo-, and enantioselective synthesis of a small library of spiropyrrolizidineoxindolesvia a four-component 1,3-dipolar cycloaddition reaction of azomethine ylides, derived from isatin, with electron-deficient dipolarophilewas described. the process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendatebis(imine)–cu(...

Dipolar Bose and Fermi gases, which are currently being studied extensively experimentally and theoretically, interact through anisotropic, long-range potentials. Here, we replace the long-range potential by a zerorange pseudopotential that simplifies the theoretical treatment of two dipolar particles in a harmonic trap. Our zero-range pseudopotential description reproduces the energy spectrum ...