Dear Nick, Thank you. I'll read the paper.
Leone Carmo Garcia 2015-08-19 14:36 GMT-03:00 Nick Papior <[email protected]>: > > > 2015-08-19 17:14 GMT+00:00 leoqmc . <[email protected]>: > >> Dear Nick, >> >> I prepared my inputs following your tips and test inputs. I'm waiting for the >> calculations to complete. But one question remains. >> >> 1) I want to get the transport properties in a single molecule and not >> added vacuum in either direction (as the tests that you recommended). The >> results will not be influenced by the "images" of my device? >> > Sure they will. :) > >> >> >> 2) I have seen examples that use large vacuum in the x and y directions. When >> this is recommended? >> > This is a drawback of the supercell approach, however, please look through > litterature for this. > This article touches upon that: 10.1103/PhysRevB.72.033401, as well as how > to circumvent 1). > >> >> >> From already thank you very much. >> >> Leone Carmo Garcia >> >> 2015-08-19 8:47 GMT-03:00 leoqmc . <[email protected]>: >> >>> Dear Nick, >>> >>> I am very grateful for your help. I will follow the tips. >>> >>> Leone Carmo Garcia >>> >>> 2015-08-18 16:42 GMT-03:00 Nick Papior <[email protected]>: >>> >>>> >>>> >>>> 2015-08-18 19:27 GMT+00:00 leoqmc . <[email protected]>: >>>> >>>>> Dear Nick and transiesta users, >>>>> >>>>> I am interested in transport calculations in single-molecule two-probe >>>>> systems[Au(111)-Molecule-Au(111)]. I searched in the list for the >>>>> following >>>>> questions, but I think that these questions were not explicitly solved for >>>>> a beginner. Please help me. >>>>> >>>>> 1) Charge: The Molecule is charged(charge +2). Not make sense uses the >>>>> option (NetCharge 2.0) in the transiesta calculation, since that the >>>>> charge >>>>> will be screened. I'm right? >>>>> >>>> No that will most likely not work, currently this is not an easy task. >>>> >>>>> >>>>> 2) Setup for the electrodes: >>>>> a) The third lattice's vector (z-direction) should have length >>>>> minimal possible, namely it should be enough for the atoms+basis >>>>> functions. >>>>> I'm right? >>>>> >>>> In your case, make the z-direction periodic. >>>> >>>>> b) The lattice's vectors in x,y direction should include large >>>>> vacuum (~20 Angstroms). I'm right? >>>>> >>>> No, not necessarily, here you can also impose periodicity. Please look >>>> at the examples in the test directory, an example of gold, gold-chain, gold >>>> is shown. That could be the basis for your further geometry creation. See >>>> example ts_au_100, both the repetition and non-repeated structure. >>>> >>>>> c) Usually you use how many units ("N") of the electrodes (N * >>>>> ABC)? >>>>> >>>> In your 111 direction I would think a single ABC stacking should be >>>> enough. This depends on your basis range, you need to check this your-self. >>>> >>>>> >>>>> 3) Setup for complete device (Electrodes + Molecule): >>>>> >>>>> a) My electrodes are equal. In this case it is mandatory to >>>>> include vacuum in the z direction, such that the device is not affected by >>>>> their image in the calculation of siesta prior to the calculation of >>>>> transiesta? >>>>> >>>> Please re-read 2a. If electrodes are the same, having a periodic setup >>>> is far better than the alternative. Again refer to the example as suggested >>>> in 2b. >>>> >>>>> >>>>> Thanks in advance. >>>>> >>>>> Leone Carmo Garcia >>>>> >>>> >>>> >>>> >>>> -- >>>> Kind regards Nick >>>> >>> >>> >> > > > -- > Kind regards Nick >
