Nanothermodynamics of metal nanoparticles

2014 ◽  
Vol 5 (7) ◽  
pp. 2605-2624 ◽  
Author(s):  
Zhen Hua Li ◽  
Donald G. Truhlar
Keyword(s):  
Free Energy ◽  
Metal Nanoparticles ◽  
Computational Chemistry ◽  
Structural Stability ◽  
Phase Changes ◽  
Aluminum Nanoparticles ◽  
Energy Functions ◽  
Thermodynamic Characterization

This article presents a perspective on thermodynamic characterization of metal nanoparticles by computational chemistry. Topics emphasized include structural stability, phases, phase changes, and free energy functions of aluminum nanoparticles.

scholarly journals DNA Modified with Metal Nanoparticles: Preparation and Characterization of Ordered Metal-DNA Nanostructures in a Solution and on a Substrate

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Nina Kasyanenko ◽  
Mikhail Varshavskii ◽  
Eugenii Ikonnikov ◽  
Evgenii Tolstyko ◽  
Roman Belykh ◽  
...  
Keyword(s):  
Metal Nanoparticles ◽  
Silicon Surface ◽  
Discharge Plasma ◽  
Silver Ions ◽  
Dna Interaction ◽  
Silver Nanoclusters ◽  
Aluminum Nanoparticles ◽  
Dna Nanostructures ◽  
Dna Strands

DNA interaction with silver and aluminum nanoparticles in a solution has been investigated with the AFM, SEM, dynamic light scattering, viscometry, and spectral methods. The comparison of DNA interaction with nanoparticles synthesized by the reduction of Ag+ions and with nanoparticles obtained by the electric discharge plasma method was done. DNA metallization in a solution and onn-silicon surface with metal nanoparticles or by the reduction of silver ions after their binding to DNA was executed and studied. It was shown that DNA strands with regular location of silver or aluminum nanoparticles can be prepared. The conditions for the formation of silver nanoparticles and silver nanoclusters on DNA were analyzed.

Thermodynamic characterization of liquid alloys with demixing tendency: Bi–Ga

2008 ◽  
Vol 99 (1) ◽  
pp. 18-23 ◽  
Author(s):  
Beatrix Huber ◽  
Klaus W. Richter ◽  
Hans Flandorfer ◽  
Adolf Mikula ◽  
Herbert Ipser
Keyword(s):  
Liquid Alloys ◽  
Thermodynamic Characterization

Thermodynamic Characterization of Ruthenium β-Diketonate Complex Ru(thd)3 as a Precursor for the CVD Preparation of Coatings

2020 ◽  
Vol 65 (5) ◽  
pp. 747-751
Author(s):  
S. V. Sysoev ◽  
T. M. Kuzin ◽  
L. N. Zelenina ◽  
K. V. Zherikova ◽  
N. V. Gelfond
Keyword(s):  
Thermodynamic Characterization

Molecular orientation of liquid aliphatic hydrocarbons on the surface and at the interface with water

1989 ◽  
Vol 54 (12) ◽  
pp. 3171-3186 ◽  
Author(s):  
Jan Kloubek
Keyword(s):  
Free Energy ◽  
Surface Free Energy ◽  
Molecular Orientation ◽  
Phase Changes ◽  
Aliphatic Hydrocarbons ◽  
Water Molecules ◽  
Free Energies ◽  
Dispersion Component ◽  
System Water ◽  
Orientation Of Molecules

The validity of the Fowkes theory for the interaction of dispersion forces at interfaces was inspected for the system water-aliphatic hydrocarbons with 5 to 16 C atoms. The obtained results lead to the conclusion that the hydrocarbon molecules cannot lie in a parallel position or be randomly arranged on the surface but that orientation of molecules increases there the ration of CH3 to CH2 groups with respect to that in the bulk. This ratio is changed at the interface with water so that the surface free energy of the hydrocarbon, γH, rises to a higher value, γ’H, which is effective in the interaction with water molecules. Not only the orientation of molecules depends on the adjoining phase and on the temperature but also the density of hydrocarbons on the surface of the liquid phase changes. It is lower than in the bulk and at the interface with water. Moreover, the volume occupied by the CH3 group increases on the surface more than that of the CH2 group. The dispersion component of the surface free energy of water, γdW = 19.09 mJ/m2, the non-dispersion component, γnW = 53.66 mJ/m2, and the surface free energies of the CH2 and CH3 groups, γ(CH2) = 32.94 mJ/m2 and γ(CH3) = 15.87 mJ/m2, were determined at 20 °C. The dependence of these values on the temperature in the range 15-40 °C was also evaluated.

Synthesis and characterization of a series of 1-methyl-4-[2-aryl-1-diazenyl]piperazines and a series of ethyl 4-[2-aryl-1-diazenyl]-1-piperazinecarboxylates

2004 ◽  
Vol 82 (8) ◽  
pp. 1294-1303 ◽  
Author(s):  
Vanessa Renée Little ◽  
Keith Vaughan
Keyword(s):  
Free Energy ◽  
Chemical Shifts ◽  
Linear Free Energy Relationship ◽  
Piperazine Ring ◽  
Linear Free Energy ◽  
In Series ◽  
Methylene Groups ◽  
Diazonium Coupling ◽  
The Difference

1-Methylpiperazine was coupled with a series of diazonium salts to afford the 1-methyl-4-[2-aryl-1-diazenyl]piperazines (2), a new series of triazenes, which have been characterized by 1H and 13C NMR spectroscopy, IR spectroscopy, and elemental analysis. Assignment of the chemical shifts to specific protons and carbons in the piperazine ring was facilitated by comparison with the chemical shifts in the model compounds piperazine and 1-methylpiperazine and by a HETCOR experiment with the p-tolyl derivative (2i). A DEPT experiment with 1-methylpiperazine (6) was necessary to distinguish the methyl and methylene groups in 6, and a HETCOR spectrum of 6 enabled the correlation of proton and carbon chemical shifts. Line broadening of the signals from the ring methylene protons is attributed to restricted rotation around the N2-N3 bond of the triazene moiety in 2. The second series of triazenes, the ethyl 4-[2-phenyl-1-diazenyl]-1-piperazinecarboxylates (3), have been prepared by similar diazonium coupling to ethyl 1-piperazinecarboxylate and were similarly characterized. The chemical shifts of the piperazine ring protons are much closer together in series 3 than in series 2, resulting in distortion of the multiplets for these methylenes. It was noticed that the difference between these chemical shifts in 3 exhibited a linear free energy relationship with the Hammett substituent constants for the substituents in the aryl ring. Key words: triazene, piperazine, diazonium coupling, NMR, HETCOR, linear free energy relationship.

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