Webinar32 - Energy Decomposition Analysis in Q-Chem

TABLE OF CONTENTS OF VIDEO (WITH LINKS) OVERVIEW 1:35 EDA introduction 3:53 ALMO-EDA in Q-Chem 5:30 Background: Accuracy of DFT for NCI 7:25 The original ALMO-ADA scheme 9:06 Overview of the ALMO-ADA 10:04 Polarization with truncated fragment virtuals 12:08 Decomposition of the FRZ energy SECOND GENERATION ALMO-EDA 13:45 The second generation ALMO-EDA 15:07 Job control for "EDA2" 17:44 EDA2 sample job 19:18 A "patch" for unrestricted systems 21:34 THE "ADIABATIC" ALMO-EDA 21:36 Limitations of the conventional EDA methods 23:11 ALMO-EDA in the "adiabatic" picture 24:35 Application: the NH3-BH3 complex 26:47 Application: blue vs. red shifting H-bonds 28:20 "Adiabatic" EDA in Q-Chem 5 30:10 "Adiabatic" EDA sample job: FRZ 31:25 "Adiabatic" EDA sample job: POL 31:51 RECENT EXTENSIONS TO MP2, EXCITED STATES, AND CHEMICAL BONDS 32:03 The MP2-ALMO-EDA scheme 34:04 MP2-EDA application 34:50 MP2-EDA sample job 35:49 EDA for excited-state interactions 37:55 . EDA for exciplexes 39:52 Further generalization for excimers 41:44 Application example: the perylene excimer 43:15 Excited-state EDA sample job: exciplex case 44:52 Excited-state EDA sample job: excimer case 46:11 ALMO-EDA for single bonds 48:27 Unraveling the "fingerprints" of chemical bonds 49:33 Acknowledgements 50:13 Q&A Summary: Energy decomposition analysis (EDA) is a category of methods that can separate a total intermolecular interaction into physically meaningful components such as permanent electrostatics, Pauli repulsion, dispersion, polarization, and charge transfer, which thus can provide valuable insights into the nature of intermolecular interactions. In this webinar, I am going to introduce the family of EDA methods based on absolutely localized molecular orbitals (ALMOs), which is a unique feature of the Q-Chem software package. I will first focus on the second-generation ALMO-EDA method (“EDA2”), which is considered as a significant improvement upon the original scheme available in earlier versions of Q-Chem. Then I will go through several novel features that are recently just available, including the “adiabatic” ALMO-EDA (in contrast to the conventional “vertical” EDA) for analyzing the effects of intermolecular interactions on molecular properties, the MP2-ALMO-EDA, and the extension of ALMO-EDA to interactions involving excited-state molecules and bonded interactions. The practical aspects will be covered by going through several sample input files associated with these features, and a general discussion on how these methods should be chosen and used will be provided.