scholarly journals Nonequilibrium spectral functions from multiterminal steady-state density functional theory

2019 ◽  
Vol 100 (8) ◽  
Author(s):  
Stefan Kurth ◽  
David Jacob ◽  
Nahual Sobrino ◽  
Gianluca Stefanucci
Keyword(s):  
Density Functional Theory ◽  
Steady State ◽  
Density Functional ◽  
State Density ◽  
Spectral Functions ◽  
Functional Theory

Spin-dependent electron transport through a Mn-phthalocyanine molecule — A steady-state density functional theory (SS-DFT) study

2016 ◽  
Vol 94 (12) ◽  
pp. 1002-1005 ◽  
Author(s):  
Shuanglong Liu ◽  
Yongjie Xi ◽  
Na Guo ◽  
Kah Meng Yam ◽  
Chun Zhang
Keyword(s):  
Density Functional Theory ◽  
Steady State ◽  
Density Functional ◽  
Electron Tunneling ◽  
State Density ◽  
Functional Theory ◽  
Tunneling Mechanism ◽  
Filtering Efficiency ◽  
Phthalocyanine Molecule ◽  
Majority Spin

We generalize the recently proposed steady-state density functional theory (SS-DFT) to spin-dependent cases and theoretically investigate the electronic and transport properties of a Mn-phthalocyanine molecule sandwiched between two graphene nanoribbon leads. The junction filters spin-up (minority spin) electrons while allowing spin-down (majority spin) electrons to pass with a filtering efficiency of about 99.5% at low biases. The spin-down electrons are found to tunnel through the junction via the HOMO orbital of the Mn-phthalocyanine molecule. Detailed analysis of the spin-dependent electron tunneling mechanism as well as the electronic/magnetic properties of the junction is presented.

scholarly journals Ground- and excited-state characteristics in photovoltaic polymer N2200

RSC Advances ◽  
2021 ◽  
Author(s):  
Guanzhao Wen ◽  
Xianshao Zou ◽  
Rong Hu ◽  
Jun Peng ◽  
Zhifeng Chen ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Excited State ◽  
Steady State ◽  
Excited States ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Time Dependent ◽  
Functional Theory ◽  
Time Resolved ◽  
Dependent Density

Ground- and excited-states properties of N2200 have been studied by steady-state and time-resolved spectroscopies as well as time-dependent density functional theory calculations.

scholarly journals Assessing the Performance of Density Functional Theory Methods on the Prediction of Low-Frequency Vibrational Spectra

2020 ◽  
Author(s):  
Peter Banks ◽  
Zihui Song ◽  
Michael Ruggiero
Keyword(s):  
Density Functional Theory ◽  
Vibrational Spectra ◽  
Density Functional ◽  
Low Frequency ◽  
Intermolecular Forces ◽  
State Density ◽  
Basis Set ◽  
Valuable Insight ◽  
Great Success ◽  
Functional Theory

The low-frequency (terahertz) dynamics of condensed phase materials provide valuable insight into numerous bulk phenomena. However, the assignment and interpretation of experimental results requires computational methods due to the complex mode-types that depend on weak intermolecular forces. Solid-state density functional theory has been used in this regard with great success, yet the selection of specific computational parameters, namely the chosen basis set and density functional, has a profound influence on the accuracy of predicted spectra. In this work, the role of these two parameters is investigated in a series of organic molecular crystals, in order to assess the ability of various methods to reproduce intermolecular forces, and subsequently experimental terahertz spectra. Specifically, naphthalene, oxalic acid, and thymine were chosen based on the varied intermolecular interactions present in each material. The results highlight that unconstrained geometry optimizations can be used as an initial proxy for the accuracy of interatomic forces, with errors in the calculated geometries indicative of subsequent errors in the calculated low-frequency vibrational spectra, providing a powerful metric for the validation of theoretical results. Finally, the origins of the observed shortcomings are analyzed, providing a basic framework for further studies on related materials.

Sign in / Sign up

Export Citation Format

Share Document