The purpose of this investigation was directed to propose sensitive, accurate and reproducible methods of analysis that can be applied to determine distigmine bromide (DTB), cyclopentolate hydrochloride (CPHC), diaveridine hydrochloride (DVHC) and tetrahydrozoline hydrochloride (THHC) drugs in pure form and pharmaceutical preparations via charge-transfer complex formation with 7,7,8,8-tetracyan...

Since chemical methods so far proposed for vitamins D determination commonly suffer from coexistence of interfering substances and hence from requirement of designing tedious purifica tion steps, a more simple analytical procedure without such pre-treatment has been strongly desired. During the course of our study on a gas-liquid chromatographic determination of vitamins D (1), efforts were als...

The principal (13)C chemical-shift values for the pi-[TCNE](2)(2-) dimer anion within an array of counterions have been measured to understand better the electronic structure of these atypical chemical species in several related TCNE-based structures. The structure of pi-[TCNE](2)(2-) is unusual as it contains two very long C-C bond lengths (ca. 2.9 Angstroms) between the two monomeric units an...

In the growing field of spintronics, development of semiconducting magnets is a high priority. Organic-based molecular magnets are attractive candidates since their properties can be tailor-made by organic chemistry. Other advantages include low weight and low temperature processing. Vanadium tetracyanoethylene, V(TCNE)x, x~2, is particularly interesting since it is one of very few semiconducti...

H NMR line-shape measurements have been performed in the linear chain molecule-based ferrimagnet ❅MnTFPP★❅TCNE★➉xPhMe 7 TFPP✺tetrakis 7 4-fluorophenyl ✦ porphinato; TCNE✺tetracyanoethylene ✦ as a function of temperature. Hyperfine shifts of opposite sign were observed indicating the presence of two oppositely hyperfine couplings, predominantly between the Mn ions and the H nuclei of the planar ...

Negative ion images generated by tetracyanoethylene (TCNE) under inverted field conditions in a field ion microscope have been investigated in more detail. The experiments confirm previous findings / I / and reveal further unique ionization phenomena such as the discontinuous development of ring structures in the ion image, the oscillation of rings in size and switching between different ion em...

The first step of electrophilic aromatic substitution reactions generally involves the formation of charge transfer complexes. Tetracyanoethylene (TCNE) in the presence of aromatic amines forms π-type complexes that subsequently lead to tricyanovinylation reaction. Although this kind of reaction was investigated in the past, the spectroscopic characterization of the charge transfer complexes is...

Prediction of the relative stabilities and phase transition behavior of molecular crystalline polymorphs is highly coveted as distinct phases can possess different physical and chemical properties while having similar energies. Crystalline tetracyanoethylene (TCNE, C6N4) is known to exhibit rich solid state phase behavior under different thermodynamic conditions, as demonstrated by a wealth of ...

Dimeric forms of norbornadiene and benzonorbornadiene were synthesized starting with known monobromide derivatives. The Diels-Alder cycloaddition reaction of dimers with TCNE and PTAD was investigated and new norbornenoid polycyclics were obtained. All compounds were characterized properly using NMR spectroscopy.