Pentavalent P…N Phosphorus Bonding in the Heterodimers of POCl3…Nitrogen Bases: Evidence from Matrix IsolationInfrared Spectroscopy and Ab Initio Computations

Among transition metal carbides and nitrides, zirconium, and hafnium compounds are the most stable and have the highest melting temperatures. Here we review published data on phases and phase equilibria in Hf-Zr-C-N-O system, from experiment and ab initio computations with focus on rocksalt Zr and Hf carbides and nitrides, their solid solutions and oxygen solubility limits. The systematic experimental studies on phase equilibria and thermodynamics were performed mainly 40–60 years ago, mostly for binary systems of Zr and Hf with C and N. Since then, synthesis of several oxynitrides was reported in the fluorite-derivative type of structures, of orthorhombic and cubic higher nitrides Zr3N4 and Hf3N4. An ever-increasing stream of data is provided by ab initio computations, and one of the testable predictions is that the rocksalt HfC0.75N0.22 phase would have the highest known melting temperature. Experimental data on melting temperatures of hafnium carbonitrides are absent, but minimum in heat capacity and maximum in hardness were reported for Hf(C,N) solid solutions. New methods, such as electrical pulse heating and laser melting, can fill the gaps in experimental data and validate ab initio predictions.

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Clustering, microalloying and mechanical properties in Cu/Zr-based glassy models by molecular dynamics simulations and ab-initio computations

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2011.11.038 ◽

2012 ◽

Vol 536 ◽

pp. S65-S69 ◽

Cited By ~ 17

Author(s):

Ch.E. Lekka ◽

G.B. Bokas ◽

G.A. Almyras ◽

D.G. Papageorgiou ◽

G.A. Evangelakis

Keyword(s):

Mechanical Properties ◽

Molecular Dynamics ◽

Ab Initio ◽

Molecular Dynamics Simulations ◽

Ab Initio Computations ◽

Dynamics Simulations

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Spectroscopic investigations and ab initio computations of the dye Chromotrope 2R

Solid State Sciences ◽

10.1016/j.solidstatesciences.2009.03.022 ◽

2009 ◽

Vol 11 (7) ◽

pp. 1275-1282 ◽

Cited By ~ 17

Author(s):

M. Snehalatha ◽

C. Ravikumar ◽

I. Hubert Joe

Keyword(s):

Ab Initio ◽

Spectroscopic Investigations ◽

Chromotrope 2R ◽

Ab Initio Computations

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Strong proton-shared hydrogen bonding in a methyl imidazole⋯HCl complex: evidence from matrix isolation infrared spectroscopy and ab initio computations

New Journal of Chemistry ◽

10.1039/d0nj00029a ◽

2020 ◽

Vol 44 (17) ◽

pp. 7116-7128 ◽

Cited By ~ 1

Author(s):

Shubhra Sarkar ◽

P. K. Sruthi ◽

N. Ramanathan ◽

K. Sundararajan

Keyword(s):

Hydrogen Bonding ◽

Infrared Spectroscopy ◽

Ab Initio ◽

Matrix Isolation ◽

Methyl Imidazole ◽

Ab Initio Computations

Evidence for proton-shared hydrogen bonding is provided in a methyl imidazole⋯HCl complex using matrix isolation infrared spectroscopy and ab initio computations.

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