Dear lammps users,

Is there any option in lammps to identify angles ( angles of unitcell ) especially after phase transformation and structural change?

Can anyone tell me a way to calulate lattice parameters and angles?

Your answers would be so helpful.

Best,

Soroush

Dear lammps users,

Is there any option in lammps to identify angles ( angles of unitcell )

especially after phase transformation and structural change?

Can anyone tell me a way to calulate lattice parameters and angles?

please have a closer look at the documentation.

it is all there:

http://lammps.sandia.gov/doc/Section_howto.html#howto_12

axel.

If you mean the shape of the entire simulation box, then

Axel's pointer to the doc pages gives you the necessary

formulas. If you mean identify the crystal orientation

of some small group of atoms within the simulation box,

then the closest thing is the compute centro/atom or

compute cna/atom commands which operate on

an atom's local environment.

Steve

Dear Axel and Steve,

I have a multi-type component system so as written in the cna/atom command, the command is not useful for more than one type atoms.

Regarding to the shape of the entire box, Axel’s pointer to the doc pages gives insights to visualizing the dump file. I do it by VMD. But I do not know how I can calculate the exact lengths and angles. I am searching for any command, any formula or whatever which helps me, if there is.

your answer would be so helpful.

Soroush

Dear Axel and Steve,

I have a multi-type component system so as written in the cna/atom command,

the command is not useful for more than one type atoms.

Regarding to the shape of the entire box, Axel's pointer to the doc pages

gives insights to visualizing the dump file. I do it by VMD. But I do not

know how I can calculate the exact lengths and angles. I am searching for

are you kidding??? have you considered reading the VMD documentation?

any command, any formula or whatever which helps me, if there is.

your answer would be so helpful.

if only your question would be helpful, too...

so what kind of angles *exactly* do you need.

those of the simulation cell, or those between

selected atoms? and if the latter, please explain

in more detail what you want to compute. remember

that we are no mindreaders. what may be obvious

to you is easily confusing to us. all that is detectable

from reading your e-mails is that you want to

compute "some" angles and "some" lengths.

if you want to be a proper researcher, you have

to be able to communicate your thoughts and

ideas precisely and lucidly.

axel.

I am sorry for my questions that seemed vague to you.

I am studying the phase transformation of a system. The initial lattice

structure has these axial lengths and interaxial angles : a≠b≠c ,

alpha=gamma=90 , beta=98. After thermal cycles, I expect a new structure. So

I have to identify the new lattice parameters and interaxial angles of the

lattice structure.

ok. in this case you already *did* get an answer.

just re-read the e-mail thread.

axel.