N-acylation was studied as a method for reducing the LUMO energy levels of benzodipyrrolidone-based polymers. The N-acylated polymers showed reduced LUMO levels and improved reversibility of reductive doping compared with N-alkylated polymers. This method may also apply in other conjugated polymers with lactam repeating units.

We studied the UV-vis absorption and fluorescence in solution/solid states of [n]cycloparaphenylene ([n]CPP: n = 9, 12, 14, 15, and 16), and conducted theoretical studies to better understand the experimental results. The representative experimental findings include (i) the most intense absorption maxima (λ(abs1)) display remarkably close values (338-339 nm), (ii) the longest-wavelength absorpt...

using the computational methods, the interaction effect of tyrosine amino acid on graphene wasinvestigated. for this purpose, the density functional theory (dft) in the ground state of 6-31gwas used, and the interaction effects of tyrosine on graphene was investigated through attachmentto three different base positions. different parameters such as energy levels, the amount ofchemical shift in ...

In the quantum theory ·of the electrnnic st:riucture of molecules, · the diffe., rence between the energy of the highest occupied molecular orbital (HOMO) and the energy of the lowest unoccupied molecular orbital (LUMO) the so-called »HOMO-LUMO separation« plays an important role1 • We shall denote this quantity by S. Relatively little has been done tin elucidating the relationship between mole...

in this study the hardness swct was calculated with b3lyp,hf method and 3-21g,6-31g,6-311g basis set .then it was investigated with the best method(b3lyp) and basis set(6-31g) to study the adsorption effects co2 on the hardness of swcnt with gap homo-lumo in two shape: horizontal, vertical and top-center-bridge and we also provide the effects of co2 adsorption on the electronic properties(dos) ...

Quantum mechanical calculations are performed on 116 conformers of the protein ubiquitin (Lange et al., Science 2008, 320, 1471–1475). The results indicate that the heat of formation (HOF), dipole moment, energy of the frontier orbitals HOMO and LUMO, and HOMO-LUMO gap fluctuate within their corresponding ranges. This study thus provides a link between the conformational dynamics of a protein a...

UNLABELLED Many chemical concepts hinge on the notion of an orbital called the lowest unoccupied molecular orbital, or LUMO. This hypothetical orbital and the much more concrete highest occupied molecular orbital (HOMO) constitute the two "frontier orbitals", which rationalize a great deal of chemistry. A viable LUMO candidate should have a sensible energy value, a realistic shape with amplitud...

Porphyrins are widely used as dye molecules in solar cells. Knowing the energies of their frontier orbitals is crucial for optimizing the energy level structure of solar cells. We use near edge x-ray absorption fine structure (NEXAFS) spectroscopy to obtain the energy of the lowest unoccupied molecular orbital (LUMO) with respect to the N(1s) core level of the molecule. A systematic energy shif...