Hi,everyone!
Recently I read a paper “Conductance through short DNA molecules”, published in J. Phys. Chem. C used ATK 2008.10. I am calculating one system very similar to their model(attached): four base pairs are inserted two Au electrodes, and the DNA molecule is situated at about 3.5 Å parallel to each Au surface. My applied version is ATK 2008.02. The author obtained very ideal I-V curve. But for the similar geometry, I obtained very odd results, as following:
#I-V Bias (Volt) Current (Ampere)
#I-V 0.0 0.0000
#I-V 0.1 1.60e-10
#I-V 0.2 9.02e-9
#I-V 0.3 5.72e-8
#I-V 0.4 1.73e-9
I feel these results are very unbelievable. The calculated I-V curve is abnormal. And I think this is absolutely not the negative differential resistance effect.
I also consulted the author for more calculate details. He told me the basis set functions in ATK should be changed for this weak interacted system. But I not dare to change this parameter due to not be familiar with the ATK computation algorithms. I try my best for a long time but the results still are unbelievable. I almost despaired.
I hope someone can help me to solve this trouble. Thanks a lot in advance.
The geometry model and my calculated details are attached.
