A systematic investigation on electronic band structure of a series of isoreticular metal−organic frameworks (IRMOFs) using density functional theory has been carried out. Our results show that halogen atoms can be used as functional groups to tune not only the band gap but also the valence band maximum (VBM) in MOFs. Among halogen atoms (F, Cl, Br, I), iodine is the best candidate to reduce th...

The effect of a substituent group in dimeric complexes of benzene with ethylene and its four derivatives on the intermolecular CH/π interaction was studied theoretically. The hydrogen-bonding nature of the CH/π interaction is confirmed by the bond critical point analysis within the atoms-in-molecules (AIM) theory. It has been found that the CH · · · π access angle depends on the exchange repuls...

Hydrogen bond (H-bond) covalency has recently been observed in ice and liquid water, while the penetrating molecular orbitals (MOs) in the H-bond region of most typical water dimer system, (H2O)2, have also been discovered. However, obtaining the quantitative contribution of these MOs to the H-bond interaction is still problematic. In this work, we introduced the orbital-resolved electron densi...

The geometries of 48 isomers of SiHmPHn (m + n ) 0-5), SiHmPHnSiHo (m + n + o ) 0-7), and (SiH3)3P have been optimized at the MP2/6-31G(d) level of theory. Silylenes and cyclic structures dominate the compounds with low numbers of hydrogens; nevertheless, there are several examples of silicon-phosphorus multiple bonding. Relative energies, heats of formation, and bond dissociation energies have...

Investigation of the properties of MnxGa1-xN semiconductor alloy is performed on the basis of LCAO electron band structure of this semiconductor. The authors model this alloy on the basis of Mn substitutions on Ga sites and it is identified that the ternary semiconductor MnxGa1-xN has two tetrahedral binary constituents – GaN and MnN. It is found that the sp 3 hybrid orbital of the N atom attra...

A theoretical DFT study was employed to investigate the different aspects of electronic structure of the salt of 1,1/(ethane-1,2-diyl)dipyridiniumbisiodate. The interactions between different molecular orbitals were considered by using DFT method. The results from the quantum mechanical calculations were then used to determine the role of donoracceptor interactions on the oxidation strength of ...

A new implementation of density functional theory (DFT), namely orbital-corrected orbital-free (OO) DFT, has been developed. With at most two non-self-consistent iterations, OO-DFT accomplishes the accuracy comparable to fully self-consistent Kohn-Sham DFT as demonstrated by its application on the cubic-diamond Si and the face-centered-cubic Ag systems. Our work provides a new impetus to furthe...

The benzene and benzene dimer cations are studied using the equation-of-motion coupled-cluster model with single and double substitutions for ionized systems. The ten lowest electronic states of the dimer at t-shaped, sandwich, and displaced sandwich configurations are described and cataloged based on the character of the constituent fragment molecular orbitals. The character of the states, bon...

Dielectric properties of the hydrogen-bonded material, 5-bromo-9-hydroxyphenalenone (C(13)H(7)O(2)Br; BrHPLN), are investigated theoretically by means of electronic structure calculations and Monte Carlo simulations. The density functional calculations of BrHPLN crystals have revealed that the polarization per one molecule can be about 1.7 times larger than that of the isolated monomer. It is a...

The crystal structure of four lutidinium chloranilates, (CH3)2C6H3NH + C6HO4Cl2 , was determined by single crystal X-ray diffraction at room temperature. 2,4-lutidinium chloranilate (I): triclinic, P1̄ (#2), Z = 2, a = 11.401(2), b = 11.639(2), c = 5.1588(8) Å, = 91.899(15) , = 90.104(14) , and = 83.355(16) , 2,5-lutidinium chloranilate (II): monoclinic, P21/c (#14), Z = 4, a = 7.709(2), b = 11....