Questions tagged [water]
For modeling of H2O or H2O clusters.
9
questions
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Simulating autoionization of small molecules using DFT or AIMD
From what I’m reading, simulation of autoionization in liquid substances is hard to do using gas phase DFT or AIMD[1][2][3]. I am using ORCA to do my work and I must confess that I’m shocked to see ...
3
votes
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answers
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MD calculations for RO in the materials studio software
To study the SiO2, polyamide and two layer SiO2-polyamide as the membranes in the reverse osmosis desalination of saline water I used the Materials Studio software to model the systems. My question is ...
11
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0
answers
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Applicability of GFN-FF force field and other xTB methods for dynamics of ions in water
I am working on a project on water clusters with ions in them. One of the problems that I ran into quite early on was that good parameters are not available for highly charged ions such as $\ce{Al^3+}$...
7
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How to calculate small and wide-angle X-ray scattering spectra for the hydration shell restricted by a distance radius criteria
My main aim is to extract the SWAXS spectra for the hydration shell surrounding a solvated molecule and I am unfamiliar with the idea of excluded solvent volume. I tried looking online but many ...
10
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0
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Setup for 4-point flexible water model [closed]
I tried to search online if there are examples or suggestions on how to set up a 4-point flexible water model, such as TIP4P/2005f, qTIP4P/f, TIP4P/$\epsilon$ FLEX, etc., but there's no clear example ...
6
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1
answer
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How to obtain electron charge density per unit volume about a water molecule using SlowQuant?
@Nike Dattani's answer to How to “get my feet wet” in Density Functional Theory by simulating a water molecule using Python recommends SlowQuant. I've used the install instructions for Linux on my ...
8
votes
0
answers
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How to reproduce 2D small-angle X-ray scattering (SAXS) interferogram of water via ab-initio MD methods?
I am trying to reproduce the 2D SAXS interference pattern of bulk water via ab initio MD methods as shown in the figure below:
The main aim is to recreate figure (a) via averaging MD configurations ...
6
votes
1
answer
104
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Do we have specific benchmarks for the speed of a simulation of an empty water box with different water models?
I'm looking for a simulation of different water models (TIP3P, SPC/E, TIP4P, water models with flexible bounds) where the differences in simulation speeds on a common architecture are really seen. ...
9
votes
1
answer
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What is the state-of-the-art in current flexible water models?
Do we have water models so far which are flexible? How good can they model specific properties of water and are they currently used with force fields and in actual simulations?