• Title/Summary/Keyword: 분자역학

Search Result 480, Processing Time 0.03 seconds

Nano-slit에서 고분자 용액의 동역학에 대한 연구

  • Jeong, Da-Bin
    • Proceeding of EDISON Challenge
    • /
    • 2014.03a
    • /
    • pp.89-101
    • /
    • 2014
  • 나노 규모의 좁은 공간에서는 분자들과 벽면과의 상호작용이 커서 분자들의 거동에 큰 영향을 준다. 이와 관련하여 최근에 나노슬릿 (nano-slit)이나 나노채널(nano-channel)과 같은 제한된 공간(confined geometry)에서 DNA의 구조적, 동역학적 거동에 관한 연구가 활발히 진행 중이다. 이러한 연구에서 모티브를 얻어 많은 입자들(spheres)로 이루어진 나노슬릿(nano-slit)사이에 Leonard-Jones potential을 따르는 용매분자들과 고분자가 들어있는 시스템을 구성하여 고분자의 동역학에 관해 연구하고자 하였다. 이때 슬릿(slit)은 약간의 탄성 포텐셜을 가지는 경우와 완전히 고정되어서 움직이지 않는 경우로 나누어 실행하였다. 더불어 고분자의크기, 용매의 종류, slit 사이의 간격 등의 변화가 고분자의 동역학에 어떤 영향을 주는지 살펴보았다. 이를 통해 환경적 조건에 따른 나노슬릿(nano-slit)에서 고분자의 움직임의 양상을 이해할 수 있었다.

  • PDF

분자동역학을 이용한 전이금속 나노구조체의 특성연구

  • Yun, Gi-Hun;Jo, Min-U
    • Proceeding of EDISON Challenge
    • /
    • 2014.03a
    • /
    • pp.359-370
    • /
    • 2014
  • 두 가지 서로 다른 원소를 포함한 나노 크기의 금속클러스터가 여러 화학반응의 효과적인 촉매로 각광받고 있다. 그래서 본 연구에서는 분자동역학을 이용하여 48개로 구성된 Au-Pd 나노 금속 클러스터의 다양한 구조와 상전이 현상을 살펴보고자 한다.

  • PDF

Development of Molecular Simulation Software for the Prediction of Thermodynamic Properties (열역학 물성 예측을 위한 분자 시뮬레이션 소프트웨어의 개발)

  • Chang, Jaee-On
    • Korean Chemical Engineering Research
    • /
    • v.49 no.3
    • /
    • pp.361-366
    • /
    • 2011
  • By using Monte Carlo simulation method we developed a new molecular simulation software which can be used to predict the thermodynamic properties of organic compounds. Starting from molecular structure and intermolecular potential function, rigorous statistical mechanical principles give a probability distribution for the behavior of a system containing many molecules, which enables us to calculate macroscopic thermodynamic properties of the system. The software developed in this work, cheMC, is based on Windows platform providing with easy access. One can efficiently administrate simulations by using an intuitive interface equipped with visualization tool and chart generation. It is expected that molecular simulations supplement the equation of state approach and will play a more important role in the study of thermodynamic properties.

The Magnetic Properties and Quantum Effects of Molecular Nanomagnets (분자 자성체의 자기 특성과 양자역학적 효과)

  • Jang, Zee-Hoon
    • Journal of the Korean Magnetics Society
    • /
    • v.14 no.2
    • /
    • pp.83-88
    • /
    • 2004
  • Magnetism of molecular nanomagnet, which attracted a lot of academic attention after the discovery of the macroscopic quantum tunneling of magnetism, is reviewed. Molecular nanomagnet is metal-organic material in which magnetic ions are regularly located in the organic skeleton. Also, the interaction between the molecules is very small and those molecules form macroscopic molecular crystal in which molecules are residing at the element points in the crystal. Molecular nanomagnets show a lot of interesting features, especially, equivalence of macroscopic magnetic properties and molecular magnetic properties. In this paper, research results on molecular nanomagnet with microscopic tool like NMR are reviewed mainly. The new method to observe the quantum tunneling of magnetization discovered in Mnl2-ac with NMR is shown and the research results on the microscopic aspects of the macroscopic quantum tunneling of magnetization using the new method are shown. Also, the physical aspect of the level crossing effect which has been reported originally with NMR in molecular nanomagnet is reviewed with experiment results. The research results on the molecular nanomagnets will reveal the important information about the limit of the miniaturization of magnetic memory units and give us the basic scientific knowledge which is needed for the application for the quantum computation. Moreover, academically, many quantum mechanical theories which have not been checked the validity can be checked with experiments.

Theoretical Study on the Absorption Spectrum of a Chromophore in Liquid (용액상 색소분자의 흡수스펙트럼에 대한 이론적 연구)

  • Woo, Jung-Moon;Yang, Min-O
    • Journal of the Korean Chemical Society
    • /
    • v.52 no.1
    • /
    • pp.7-15
    • /
    • 2008
  • Molecular motion influencing the absorption spectrum of a chromophore in liquid is theoretically described by a quantum mechanical time correlation function. In the present paper, we developed a theoretical method to calculate such a quantum mechanical time-correlation function from a classical time-correlation function using semi-classical approximations. The calculated time-correlation function was combined with the second order cumulant expansion method to calculate the absorption spectrum of nile blue in acetonitrile. Reasonably good agreement with experimental spectrum was obtained. From the comparison with experimental spectrum, we concluded that the time scale of solvation dynamics of the system should be longer then 1ps and the first shell of solvent is the major contribution to the solvation dynamics.