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? 2) I have seen examples that use large vacuum in the x and y directions. When this is recommended? >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 >> > >
