Investigation of the preferential solvation and dynamical properties of Cu+ in 18.6% aqueous ammonia solution using ab initio quantum mechanical charge field (QMCF) molecular dynamics and NBO analysis

A quantum mechanical charge field (QMCF) molecular dynamics (MD) simulation has been carried out to describe the structural and dynamical properties of Cu+ ion in liquid ammonia. The first and second shells were treated by ab initio quantum mechanics at the Hartree−Fock (HF) level with the DZP-Dunning basis set for ammonia and LANL2DZ ECP basis set for Cu. The system was equilibrated for 4 ps, then the trajectory data was collected every fifth step for 20 ps at 235.15 K. The structural analysis showed that in the first solvation shell, Cu+ is solvated by 4 ammonia molecules forming a stable structure of tetrahedral with Cu-N bond length of 2.15 Å, whereas in the second solvation shell there are 29 ammonia molecules that have an average distance of 4.79 Å to Cu+ ion. Mean residence time of 3.06 ps was observed for the ammonia ligand in the second solvation shell indicating for a highly unstable structure of the solvation shell. The obtained structure of the first solvation shell from this simulation is in excellent agreement with experimental data.

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Palladium(ii) in liquid ammonia: an investigation of structural and dynamical properties by applying quantum mechanical charge field molecular dynamics (QMCF-MD)

Dalton Transactions ◽

10.1039/c7dt01548h ◽

2017 ◽

Vol 46 (29) ◽

pp. 9630-9638 ◽

Cited By ~ 6

Author(s):

Muhammad Saleh ◽

Thomas S. Hofer

Keyword(s):

Molecular Dynamics ◽

Liquid Ammonia ◽

Quantum Mechanical ◽

Charge Field ◽

Dynamical Properties ◽

Mechanical Charge

The structural and dynamical properties of Pd2+ in liquid ammonia have been investigated via quantum mechanical charge field molecular dynamics.

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The Jahn-Teller effect in mixed aqueous solution: the solvation of Cu2+ in 18.6% aqueous ammonia obtained from ab initio quantum mechanical charge field molecular dynamics

Pure and Applied Chemistry ◽

10.1515/pac-2018-1115 ◽

2019 ◽

Vol 91 (10) ◽

pp. 1553-1565 ◽

Cited By ~ 3

Author(s):

Wahyu Dita Saputri ◽

Karna Wijaya ◽

Harno Dwi Pranowo ◽

Thomas S. Hofer

Keyword(s):

Molecular Dynamics ◽

Ab Initio ◽

Aqueous Ammonia ◽

Experimental Studies ◽

Solvation Shell ◽

Basis Sets ◽

Quantum Mechanical ◽

Jahn Teller ◽

Charge Field ◽

Mechanical Charge

Abstract The solvation structure and dynamics of Cu2+ in 18.6 % aqueous ammonia have been investigated using an ab initio quantum mechanical charge field molecular dynamics (QMCF MD) simulation approach at the Hartree–Fock (HF) level of theory applying the LANL2DZ ECP and Dunning DZP basis sets for Cu2+, ammonia and water, respectively. During a simulation time of 20 ps, only NH3 molecules are observed within the first solvation shell of Cu2+, resulting in the formation of an octahedral [Cu(NH3)6]2+ complex. While no exchange of these ligands with the second solvation shell are observed along the simulation, the monitoring of the associated N-Ntrans distances highlight the dynamics of the associated Jahn-Teller distortions, showing on average 2 elongated axial (2.19 Å) and 4 equatorial Cu–N bonds (2.39 Å). The observed structural properties are found in excellent agreement with experimental studies. In addition, an NBO analysis was carried out, confirming the strong electrostatic character of the Cu2+–NH3 interaction.

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