scholarly journals Pt(II) Complexes with Linear Diamines—Part I: Vibrational Study of Pt-Diaminopropane

2012 ◽  
Vol 27 ◽  
pp. 403-413 ◽  
Author(s):  
Ana L. M. Batista de Carvalho ◽  
Sónia M. Fiuza ◽  
John Tomkinson ◽  
Luís A. E. Batista de Carvalho ◽  
M. Paula M. Marques

A conformational analysis of the Pt(dap)Cl2complex (-diaminopropane) was performed by vibrational spectroscopy (FTIR, Raman, and INS), coupled to quantum mechanical methods within the density functional theory (DFT) and effective core potential (ECP) approaches. A complete spectral assignment of the system was achieved, due to the combined use of all available vibrational spectroscopic techniques. A good agreement was found between experimental and theoretical results, as well as with reported data for analogous complexes (e.g., cisplatin).

2013 ◽  
Vol 321-324 ◽  
pp. 1761-1765 ◽  
Author(s):  
Jian Ying Li ◽  
Jing Zhang ◽  
Qi Zhi Cao ◽  
Yi Fang Ouyang

The elastic constants of FeP with orthorhombic structure were calculated by using the density-functional theory method. The formation enthalpy, electronic density of states, bulk modulus, and lattice parameters of orthorhombic FeP were also calculated. All of the results are in good agreement with the experimental data and theoretical results available. The results indicate that orthorhombic FeP intermetallic compound is brittleness.


Open Physics ◽  
2008 ◽  
Vol 6 (4) ◽  
Author(s):  
Yasemin Ciftci ◽  
Kemal Colakoglu ◽  
Engin Deligoz

AbstractWe present an ab initio study of the structural, electronic and thermodynamic properties of TlX(X=P,As). The plane-wave pseudopotential approach to the density-functional theory within the LDA and GGA approximations implemented in VASP (Viena Ab-initio Simulation Package) is used. The calculated lattice parameter, elastic constants, and band structures are compared with other available theoretical results, and good agreement is obtained. In addition, we have calculated the transition pressure (P t) from zinc-blende (ZB) to (rock-salt) NaCl structures, and have examined some thermodynamic properties.


2012 ◽  
Vol 571 ◽  
pp. 292-295
Author(s):  
Ben Hai Yu ◽  
Chao Xu ◽  
Dong Chen

We report ab initio calculations of the structural, elastic and optical properties of the compound LaB6 as a function of pressure. The computation is based on the density functional theory in combination with the generalized gradient approximation functional. The calculated lattice constants and elastic moduli are compared with the theoretical results and a good agreement is found. LaB6 can retain its mechanical stability in the pressure range of 0-20GPa. Besides, the frequency-dependent dielectric function, absorption coefficient and loss function of LaB6 are also obtained. The calculated static dielectric function is 8.8 at 0GPa and 5GPa. The computed results should be testified by experiments.


2015 ◽  
Vol 233-234 ◽  
pp. 229-232 ◽  
Author(s):  
Vladimir V. Sokolovskiy ◽  
Mikhail A. Zagrebin ◽  
Y.A. Sokolovskaya ◽  
Vasiliy D. Buchelnikov

The structural and magnetic properties of Mn-based stoichiometric Heusler alloys have investigated by means of ab initio calculations in framework of the density functional theory. First principles electronic structure calculations have shown that Mn2NiZ (Z = Ga, In, Sn, Sb) alloys are ferrimagnets with antiparallel alignment between the Mn atoms. The martensitic transition can be realized in Mn2NiGa and Mn2NiSn alloys with tetragonal ratio of 1.27 and 1.16, respectively. Calculated properties are in a good agreement with available experimental data.


2012 ◽  
Vol 535-537 ◽  
pp. 214-218
Author(s):  
Qi Xin Wan ◽  
Jia Yi Chen ◽  
Zhi Hua Xiong ◽  
Dong Mei Li ◽  
Bi Lin Shao ◽  
...  

The first-principles with pseudopotentials method based on the density functional theory was applied to calculate the geometric structure, the formation energy of impurities and the electronic structure of Li-doped ZnO. In the system of Li-doped ZnO, LiZn can not result in lattice distortion. In contrast with that case, LiO and Lii result in lattice distortion after Li doping in ZnO. In Li-doped ZnO, LiO is the most unstable than the other cases. Simultaneously, Lii is more stable than LiZn according to that Lii has smaller formation energy. Furthermore, the electronic structure of Li-doped ZnO indicates that that LiZn behaves as acceptor, while Lii behaves as donor. In conclusion, in Li-doped ZnO, Lii is always in the system to compensate the acceptor. Singly doping Li in ZnO is difficult to gain p-ZnO for the self-compensation. The results are in good agreement with other calculated and experimental results.


2016 ◽  
Vol 23 (1) ◽  
pp. 286-292 ◽  
Author(s):  
Ana Umićević ◽  
Heinz-Eberhard Mahnke ◽  
Jelena Belošević-Čavor ◽  
Božidar Cekić ◽  
Gerhard Schumacher ◽  
...  

X-ray absorption spectroscopy is employed to investigate site preference and lattice relaxation around Mo, Ru, Hf, W and Re dopants in Ni3Al. The site occupation preference and the measured distances between the refractory elements as dopants and the nearest host atoms are compared with the results ofab initiocalculations within the density functional theory. Combined experimental and theoretical results indicate that Mo, Hf, W and Re atoms reside on the Al sublattice in Ni3Al, while Ru atoms occupy the Ni sublattice. A more pronounced lattice relaxation was detected in the case of Hf and Ru doping, with a strong outward relaxation of the nearest Ni and Al atoms.


2004 ◽  
Vol 832 ◽  
Author(s):  
Yuri Bonder ◽  
Chumin Wang

ABSTRACTOptical properties of birefringent porous-silicon layers are studied within the density functional theory. Starting from a (110)-oriented supercell of 32 silicon atoms, columns of atoms in directions [100] and [010] are removed and the dangling bonds are saturated with hydrogen atoms. The results show an in-plane anisotropy in the dielectric function and in the refractive index (n). The difference Δn defined as n[110] -n[001] is compared with experimental data and a good agreement is observed. Also, the possibility in determining the morphology of pores by using polarized lights is analyzed.


2007 ◽  
Vol 5 (1) ◽  
pp. 201-220 ◽  
Author(s):  
Khaled Bahgat ◽  
Abdel Ragheb

AbstractThe geometry, frequency and intensity of the vibrational bands of 8-hydroxyquinoline and its 5,7-dichloro, 5,7-dibromo, 5,7-diiodo and 5,7-dinitro derivatives were obtained by the density functional theory (DFT) calculations with Becke3-Lee-Parr (B3LYP) functional and 6-31G* basis set. The effects of chloride, bromide, iodide and nitro substituent on the vibrational frequencies of 8-hydroxyquinoline have been investigated. The assignments have been proposed with aid of the results of normal coordinate analysis. The observed and calculated spectra are found to be in good agreement.


2015 ◽  
Vol 729 ◽  
pp. 15-20
Author(s):  
Hong Bo Zhu ◽  
Dun Qiang Tan ◽  
Zhi Huang Xiong

The structural phase transitions and electronic structures of Co are investigated by using the first-principles calculation based on density-functional theory (DFT). Our calculated equilibrium structural parameters of Co are in good agreement with the available experimental data and other theoretical results. The calculated phase transition hcp-Co → fcc-Co at ca. 125.25 GPa. The magnetic moment of hcp-Co and fcc-Co drops to zero at 155 GPa and 77 GPa, respectively.


2017 ◽  
Vol 31 (11) ◽  
pp. 1750079 ◽  
Author(s):  
Chaoyan Zhang ◽  
Hua Hou ◽  
Yuhong Zhao ◽  
Xiaomin Yang ◽  
Yaqiong Guo

The structural, elastic and thermal properties of [Formula: see text]-TiAl and [Formula: see text]-Ti3Al phases in the TiAl-based alloy under pressure were reported using CASTEP program based on the density functional theory. The calculated equilibrium parameters and elastic constants are in good agreement with experimental and the available theoretical data. The results indicate that under the same pressure, the [Formula: see text] phase in the direction along [Formula: see text]-axis is easier to be compressed than the [Formula: see text] phase, while the compression along [Formula: see text]-axis of [Formula: see text] phase is larger than that of [Formula: see text] phase; when the pressure is below 20 GPa, both the two phases are elastically stable, but the [Formula: see text] phase have higher shear modulus and Young’s modulus, and the [Formula: see text] phase has better ductility and plasticity. Debye temperature, bulk modulus, thermal expansion coefficient and heat capacity of the [Formula: see text] phase and [Formula: see text] phase under high pressure and high temperature were also successfully calculated and compared using the quasi-harmonic Debye model in the present work.


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