In this paper we present the results on Raman-active modes calculation in achiral (n, n) and (n, 0) carbon nanotubes (CNTs). vibrational spectra are derived as the eigenvalues of corresponding dynamical matrix at the Γ-point of Brillouin zone. Diagonal components and α xy (= α yx) are the only non-zero components of polarization tensor. Selection rules for Raman-active modes are determined by d...

We have studied the phase sequence and physical properties of an asymmetric bent-core material with a chiral rigid cholesteryl moiety, and a flexible achiral alkyl side chain at the other end. The combination of the achiral bent core with the chiral cholesteryl unit results in properties different from those of both the usual calamitic and bent-core materials. We find that the presence of the b...

The catalytic synthesis of nitrogen-containing heterocycles is of great importance to medicinal and synthetic chemists, and also a challenge for modern chemical methodology. In this paper, we report the synthesis of pyrazolidine derivatives through a domino aza-Michael/hemiacetal sequence with chiral or achiral secondary amines as organocatalysts. Thus, a series of achiral pyrazolidine derivati...

We consider a model for periodic patterns of charges constrained over a cylindrical surface. In particular we focus on patterns of chiral helices, achiral rings, or vertical lamellae, with the constraint of global electroneutrality. We study the dependence of the patterns' size and pitch angle on the radius of the cylinder and salt concentration. We obtain a phase diagram by using numerical and...

A general process for the high-yielding synthesis of substituted chiral and achiral α-substituted acrylates was achieved through the sequential one-pot combination of a metal-free reductive coupling reaction followed by an Eschenmoser methylenation. The proline catalyzed reaction of Meldrum's acid, aldehydes and Hantzsch ester followed by methylenation was successful with Eschenmoser's salt in ...

Reaction of the chiral crystals of the achiral amides with n-butyllithium in toluene at -80 degrees C gave optically active alcohols in 17-84% ee.

Various novel palladium(II) complexes with tunable chiral and achiral anionic counterions have been prepared from dialkylpalladium(II) agents and characterized by NMR spectroscopy and X-ray diffraction.

Mixing a chiral Cr( iii ) complex with an achiral Eu( into silica nanoparticle gave rise to simultaneous unpolarized red and polarized NIR luminescence.

Recently, we proposed a metasurface design for chiral sensing that (i) results in enhanced chiroptical signals by more than two orders of magnitude ultrathin, subwavelength, samples over uniform and accessible area, (ii) allows complete measurements the total chirality (magnitude sign both its real imaginary part), (iii) offers possibility crucial signal reversal (excitation with reversed polar...

A planar-chiral pillar[5]arene derivative containing one π-conjugated unit was prepared. Chiroptical changes were observed upon addition of the achiral guest 1,4-dicyanobutane.