Re: [gmx-users] CU2+ nonbonded parameteres (sigma and epsilon)

2019-03-16 Thread Justin Lemkul
On 3/16/19 9:06 AM, Mohsen Asadbegi wrote: Thanks for your answer, I want to simulate interaction of amyloid-beta peptide and CU(II) ion in non-bonded modes. Non-bonded parameters of some metal ions like ZN(II), CAD(II), and CA(II) are provided in CHARMM36. So what is the difference among

Re: [gmx-users] CU2+ nonbonded parameteres (sigma and epsilon)

2019-03-16 Thread Mohsen Asadbegi
Thanks for your answer, I want to simulate interaction of amyloid-beta peptide and CU(II) ion in non-bonded modes. Non-bonded parameters of some metal ions like ZN(II), CAD(II), and CA(II) are provided in CHARMM36. So what is the difference among copper ion and zinc/cadmium and calcium ions?

Re: [gmx-users] CU2+ nonbonded parameteres (sigma and epsilon)

2019-03-16 Thread Paul Bauer
Hello, Classical force fields are a bad way to describe the behaviour of transition metals such as CU2+, because they are not able to cover the behaviour of the D-orbitals with just the sigma and epsilon parameters. What are you planning to use the model for? It is possible to parametrize

[gmx-users] CU2+ nonbonded parameteres (sigma and epsilon)

2019-03-15 Thread Mohsen Asadbegi
Hi! I need to add non-bonded CU2+ ion to CHRAMM36. How can I find these parameters (sigma and epsilon)? Does it enough to define CU2+ by its charge, mass, sigma and epsilon? In addition, I want to know that what are the units of sigma and epsilon in the CHARMM36 force field? Regards, Mohsen