Deformation of 2D Materials and Interfaces

Presentations

• Programming Shape, Composition Patterns and Dynamics of 2D Transition Metal Dichalcogenide Alloys

  Invited

  March 15, 2021, 8:00 AM – March 15, 2021, 8:36 AM

  Presenters

  • David Srolovitz

    • City Univ of Hong Kong

  Authors

  • Joel M Berry

    • Lawrence Livermore National Laboratory

  • Simeon Ristić

    • University of Pennsylvania

  • Songsong Zhou

    • University of Pennsylvania

  • Jiwoong Park

    • Department of Chemistry, University of Chicago
    • University of Chicago
    • Pritzker School of Molecular Engineering, University of Chicago

  • David Srolovitz

    • City Univ of Hong Kong

  View abstract →

• Open Access Database for Engineering Complex Interfaces

  ORAL

  March 15, 2021, 8:36 AM – March 15, 2021, 8:48 AM

  Presenters

  • Eli Gerber

    • Cornell University

  Authors

  • Eli Gerber

    • Cornell University

  • Steven Torrisi

    • Department of Physics, Harvard University
    • Physics, Harvard University
    • John A. Paulson School of Engineering and Applied Sciences, Harvard University
    • Harvard University

  • Kristin Persson

    • Materials Science & Engineering, University of California, Berkeley
    • Lawrence Berkeley National Laboratory

  • Efthimios Kaxiras

    • Harvard University
    • Department of Physics, Harvard University
    • Physics, Harvard University

  • Jenny E. Hoffman

    • Harvard University
    • Department of Physics, Harvard University

  • Eun-Ah Kim

    • Cornell University
    • Department of Physics, Cornell University

  View abstract →

• First-principles studies of the energetic and electronic properties of charged defects, dopants, and complexes in 2D metal chalcogenides

  ORAL

  March 15, 2021, 8:48 AM – March 15, 2021, 9:00 AM

  Presenters

  • Richard Hennig

    • University of Florida
    • Department of Materials Science and Engineering, University of Florida
    • Materials Science and Engineering, University of Florida

  Authors

  • Anne Marie Tan

    • University of Florida

  • Yuanxi Wang

    • Pennsylvania State University
    • Penn State University

  • Qingkai Qian

    • Pennsylvania State University
    • Penn State University

  • Christoph Freysoldt

    • Max Planck Inst fuer Eisenforschung GmbH
    • Max Planck Institut für Eisenforschung

  • Shengxi Huang

    • Pennsylvania State University
    • Penn State University
    • The Pennsylvania State University

  • Richard Hennig

    • University of Florida
    • Department of Materials Science and Engineering, University of Florida
    • Materials Science and Engineering, University of Florida

  View abstract →

• Bilayer graphene stacking registry control.

  ORAL

  March 15, 2021, 9:00 AM – March 15, 2021, 9:12 AM

  Presenters

  • Lev Krainov

    • Pennsylvania State University

  Authors

  • Lev Krainov

    • Pennsylvania State University

  • Vincent Henry Crespi

    • Pennsylvania State University

  View abstract →

• Strain tuning of 2D van der Waals heterostructures

  ORAL

  March 15, 2021, 9:12 AM – March 15, 2021, 9:24 AM

  Presenters

  • Xuetao Ma

    • University of Washington

  Authors

  • Xuetao Ma

    • University of Washington

  • Zhaoyu Liu

    • University of Washington

  • Joshua Mutch

    • University of Washington

  • Takashi Taniguchi

    • National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institure for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • NIMS
    • National Institute of Materials Science
    • National Institute for Materials Science (NIMS)
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Science,1-1 Namiki
    • National Institute of Material Science
    • National Institute for Materials Science, Tsukuba, Japan
    • International Center for Materials Nanoarchitectonics, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute of Materials Science, Tsukuba, Japan
    • National Institude for Materials Science
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials
    • NIMS - Japan
    • National Institute for Materials Science ,Japan
    • National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
    • National Institute for Material Science
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science Japan
    • 8International Center for Materials Nanoarchitectonics
    • NIMS Tsukuba
    • National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP
    • National Institue for Material Science
    • National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In
    • Research Center for Functional Materials, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • International Center for Material Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials Nanoarchitectonics
    • NIMS Suguba
    • NIMS, Tsukuba, Japan
    • National Cheng Kung University
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan
    • National institute of material science
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, International Center for Materials Nanoarchitectonics
    • National Institute of Material Science, Japan
    • Tsukuba, National Institute for Materials Science

  • Kenji Watanabe

    • National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institure for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • NIMS
    • National Institute of Materials Science
    • National Institute for Materials Science (NIMS)
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute for Materials Science,1-1 Namiki
    • National Institute of Material Science
    • National Institute for Materials Science, Tsukuba, Japan
    • Research Center for Functional Materials, NIMS
    • National Institute of Materials Science, Tsukuba, Japan
    • National Institude for Materials Science
    • National Institute for Materials Science, Tsukuba, Ibaraki, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, Tsukuba 305-0044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials
    • NIMS - Japan
    • National Institute for Materials Science ,Japan
    • National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
    • National Institute for Material Science
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science Japan
    • NIMS Tsukuba
    • National Institute for Materials Science, Research Center for Functional Materials, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP
    • National Institue for Material Science
    • National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan
    • Materials, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In
    • Research Center for Functional Materials, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials nanoarchtectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • NIMS Suguba
    • NIMS, Tsukuba, Japan
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan
    • National institute of material science
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • Advanced Materials Laboratory, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science, Ibaraki, Japan
    • National Institute for Materials Science, Research Center for Functional Materials
    • National Institute of Material Science, Japan
    • Tsukuba, National Institute for Materials Science

  • Matthew Yankowitz

    • University of Washington
    • Physics, University of Washington

  • Jiun-Haw Chu

    • University of Washington
    • Department of Physics, University of Washington, Seattle
    • Department of Physics, University of Washington
    • Physics, University of Washington

  View abstract →

• Synthesis of long-range stacked rhombohedral graphene through shear and effects of temperature

  ORAL

  March 15, 2021, 9:24 AM – March 15, 2021, 9:36 AM

  Presenters

  • Jean Paul Nery

    • Graphene Laboratories, Fondazione Istituto Italiano di Tecnologia, I-16163 Genova, Italy; Dipartimento di Fisica, Università di Roma La Sapienza, I-00185 Roma, Italy

  Authors

  • Jean Paul Nery

    • Graphene Laboratories, Fondazione Istituto Italiano di Tecnologia, I-16163 Genova, Italy; Dipartimento di Fisica, Università di Roma La Sapienza, I-00185 Roma, Italy

  • Matteo Calandra

    • Universita di Trento, Povo, Italy; Graphene Labs, Fondazione Isituto Italiano di Tecnologia, Via Morego, I-16163 Genova, Italy; Sorebonne Universite, CNRS, Institut des Nanos
    • Graphene Laboratories, Fonazione Isituto Italiano di Tecnologia, I-161613 Genova, Italy; Department of Physics, University of Trento, 38123 Povo, Italy, Sorbonne University,
    • Graphene Laboratories, Fondazione Istituto Italiano di Tecnologia, I-16163 Genova, Italy, Department of Physics, University of Trento, 38123 Povo, Italy

  • Francesco Mauri

    • Dipartimento di Fisica, Università di Roma Sapienza, Rome, Italy
    • Graphene Laboratories, Fondazione Istituto Italiano di Tecnologia, 1-16163 Genova, Italy; Dipartimento di Fiscia Universita di Roma La Sapienza, I-00185 Roma, Italy
    • Graphene Laboratories, Fondazione Istituto Italiano di Tecnologia, I-16163 Genova, Italy; Dipartimento di Fisica, Università di Roma La Sapienza, I-00185 Roma, Italy
    • Università di Roma "La Sapienza"

  View abstract →

• Shear and breathing modes of all layered materials

  ORAL

  March 15, 2021, 9:36 AM – March 15, 2021, 9:48 AM

  Presenters

  • Giovanni Pizzi

    • Ecole Polytechnique Federale de Lausanne
    • Theory and Simulation of Materials (THEOS), and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Federale de Lausanne,
    • Theory and Simulation of Materials (THEOS), Faculté des Sciences et Techniques de l’Ingénieur, École Polytechnique Fédérale de Lausanne
    • THEOS, EPFL

  Authors

  • Giovanni Pizzi

    • Ecole Polytechnique Federale de Lausanne
    • Theory and Simulation of Materials (THEOS), and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Federale de Lausanne,
    • Theory and Simulation of Materials (THEOS), Faculté des Sciences et Techniques de l’Ingénieur, École Polytechnique Fédérale de Lausanne
    • THEOS, EPFL

  • Silvia Milana

    • Cambridge Graphene Centre, University of Cambridge

  • Andrea C. Ferrari

    • Cambridge Graphene Centre, University of Cambridge

  • Nicola Marzari

    • Ecole Polytechnique Federale de Lausanne
    • Theory and Simulation of Materials (THEOS), and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Federale de Lausanne
    • École Polytechnique Fédérale de Lausanne
    • Theory and Simulation of Materials (THEOS), and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Federale de Lausanne,
    • Theory and Simulation of Materials (THEOS), Faculté des Sciences et Techniques de l’Ingénieur, École Polytechnique Fédérale de Lausanne
    • THEOS, EPFL
    • École Polytechnique Fédérale de Lausanne (EPFL)
    • Theory and Simulation of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne (E
    • Theory and Simulation of Materials (THEOS), and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), EPFL, CH-1015 Lausanne, Switzerland
    • Theory and simulation of materials (THEOS), National Centre for Computational Design and Discovery of Novel Materials (MARVEL), EPFL
    • Materials Engineering, EPFL
    • Theory and Simulations of Materials (THEOS), and National Center for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Federale de Lausanne

  • Marco Gibertini

    • THEOS, EPFL
    • University of Modena & Reggio Emilia
    • University of Modena and Reggio Emilia

  View abstract →

• Electronic properties of periodically modified graphene: A first-principles study

  ORAL

  March 15, 2021, 9:48 AM – March 15, 2021, 10:00 AM

  Presenters

  • Yuta Taguchi

    • Deparrment of Physics, Tokyo Institute of Technology

  Authors

  • Yuta Taguchi

    • Deparrment of Physics, Tokyo Institute of Technology

  • Susumu Saito

    • Tokyo Institute of Technology
    • Deparrment of Physics, Tokyo Institute of Technology

  View abstract →

• The true corrugation of a h-BN nanomesh layer

  ORAL

  March 15, 2021, 10:00 AM – March 15, 2021, 10:12 AM

  Presenters

  • Matthias Muntwiler

    • Photon Science Division, Paul Scherrer Institut

  Authors

  • Luis Henrique de Lima

    • Photon Science Division, Paul Scherrer Institut

  • Thomas Greber

    • Institute of Physics, University of Zurich

  • Matthias Muntwiler

    • Photon Science Division, Paul Scherrer Institut

  View abstract →

• Surface corrugations and layer thickness dependent frictional behavior of MoS₂ – A computational study

  ORAL

  March 15, 2021, 10:12 AM – March 15, 2021, 10:24 AM

  Presenters

  • Jatin Kashyap

    • New Jersey Inst of Tech

  Authors

  • Jatin Kashyap

    • New Jersey Inst of Tech

  • Dibakar Datta

    • New Jersey Inst of Tech

  View abstract →

• Structure-property relationship of epitaxial Van der Waals interface

  ORAL

  March 15, 2021, 10:24 AM – March 15, 2021, 10:36 AM

  Presenters

  • Hiroyuki Nakamura

    • University of Arkansas

  Authors

  • Hiroyuki Nakamura

    • University of Arkansas

  • Philipp Rosenzweig

    • Max Planck Institute for Solid State Research

  • Avaise Mohammed

    • Max Planck Institute for Solid State Research

  • Kathrin Küster

    • Max Planck Institute for Solid State Research, Stuttgart, Germany
    • Max Planck Institute for Solid State Research

  • Peter Wochner

    • Max Planck Institute for Solid State Research

  • Ulrich Wedig

    • Max Planck Institute for Solid State Research

  • Hadeel Hussain

    • Diamond Light Sorce

  • Jonathan Rawle

    • Diamond Light Sorce

  • Chris Nicklin

    • Diamond Light Sorce

  • Hidenori Takagi

    • University of Tokyo (Japan)
    • Max Planck Institute for Solid State Research
    • Max Planck Institute for Solid State Research, Stuttgart, Germany

  • Ulrich Starke

    • Max Planck Institute for Solid State Research

  View abstract →

• Auxetic two-dimensional transition metal selenides and halides

  ORAL

  March 15, 2021, 10:36 AM – March 15, 2021, 10:48 AM

  Presenters

  • Jinbo Pan

    • Temple University
    • Chinese Academy of Sciences,Institute of Physics

  Authors

  • Jinbo Pan

    • Temple University
    • Chinese Academy of Sciences,Institute of Physics

  • Yan-Fang Zhang

    • Chinese Academy of Sciences,Institute of Physics

  • Jingda Zhang

    • Nankai University

  • Huta Banjade

    • Temple University

  • Jie Yu

    • Temple University

  • Liping Yu

    • University of Maine

  • Shixuan Du

    • Chinese Academy of Sciences,Institute of Physics
    • Institute of Physics and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
    • School of physical sciences, Institute of Physics and University of Chinese Academy of Sciences
    • Institute of Physics, Chinese Academy of Sciences
    • Chinese Academy of Science
    • Chinese Academy of Sciences, Institute of Physics
    • Institute of Physics & University of Chinese Academy of Sciences, Chinese Academy of Sciences

  • Adrienn Ruzsinszky

    • Physics, Temple University
    • Temple University

  • Zhenpeng Hu

    • School of Physics, Nankai University
    • Nankai University

  • Qimin Yan

    • Temple University
    • Physics, Temple University

  View abstract →

• Phonon Renormalization in Reconstructed MoS₂ Moiré superlattices

  ORAL

  March 15, 2021, 10:48 AM – March 15, 2021, 11:00 AM

  Presenters

  • Jiamin Quan

    • University of Texas at Austin
    • Department of Physics, The University of Texas at Austin
    • Department of Physics, Center of Complex Quantum Systems, University of Texas at Austin

  Authors

  • Jiamin Quan

    • University of Texas at Austin
    • Department of Physics, The University of Texas at Austin
    • Department of Physics, Center of Complex Quantum Systems, University of Texas at Austin

  • Lukas Linhart

    • Vienna University of Technology

  • Miao-Ling Lin

    • Institute of Semiconductors

  • Daehun Lee

    • University of Texas at Austin

  • Jihang Zhu

    • University of Texas at Austin
    • Department of Physics, University of Texas at Austin
    • University of Texas, Austin

  • Chun Yuan Wang

    • University of Texas at Austin

  • Wei-Ting Hsu

    • Natl Tsing Hua Univ
    • University of Texas at Austin

  • Junho Choi

    • University of Texas at Austin
    • Department of Physics, The University of Texas at Austin

  • Jacob Embley

    • University of Texas at Austin

  • Carter Young

    • University of Texas at Austin

  • Takashi Taniguchi

    • National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institure for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • NIMS
    • National Institute of Materials Science
    • National Institute for Materials Science (NIMS)
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Science,1-1 Namiki
    • National Institute of Material Science
    • National Institute for Materials Science, Tsukuba, Japan
    • International Center for Materials Nanoarchitectonics, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute of Materials Science, Tsukuba, Japan
    • National Institude for Materials Science
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials
    • NIMS - Japan
    • National Institute for Materials Science ,Japan
    • National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
    • National Institute for Material Science
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science Japan
    • 8International Center for Materials Nanoarchitectonics
    • NIMS Tsukuba
    • National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP
    • National Institue for Material Science
    • National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In
    • Research Center for Functional Materials, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • International Center for Material Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials Nanoarchitectonics
    • NIMS Suguba
    • NIMS, Tsukuba, Japan
    • National Cheng Kung University
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan
    • National institute of material science
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, International Center for Materials Nanoarchitectonics
    • National Institute of Material Science, Japan
    • Tsukuba, National Institute for Materials Science

  • Kenji Watanabe

    • National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institure for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • NIMS
    • National Institute of Materials Science
    • National Institute for Materials Science (NIMS)
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute for Materials Science,1-1 Namiki
    • National Institute of Material Science
    • National Institute for Materials Science, Tsukuba, Japan
    • Research Center for Functional Materials, NIMS
    • National Institute of Materials Science, Tsukuba, Japan
    • National Institude for Materials Science
    • National Institute for Materials Science, Tsukuba, Ibaraki, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, Tsukuba 305-0044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials
    • NIMS - Japan
    • National Institute for Materials Science ,Japan
    • National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
    • National Institute for Material Science
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science Japan
    • NIMS Tsukuba
    • National Institute for Materials Science, Research Center for Functional Materials, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP
    • National Institue for Material Science
    • National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan
    • Materials, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In
    • Research Center for Functional Materials, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials nanoarchtectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • NIMS Suguba
    • NIMS, Tsukuba, Japan
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan
    • National institute of material science
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • Advanced Materials Laboratory, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science, Ibaraki, Japan
    • National Institute for Materials Science, Research Center for Functional Materials
    • National Institute of Material Science, Japan
    • Tsukuba, National Institute for Materials Science

  • Chih-Kang Shih

    • Physics, University of Texas at Austin
    • University of Texas at Austin
    • Department of Physics, The University of Texas at Austin

  • Keji Lai

    • University of Texas at Austin
    • Department of Physics, University of Texas at Austin

  • Allan MacDonald

    • Physics, University of Texas at Austin
    • Physics Department, University of Texas at Austin
    • University of Texas at Austin
    • Department of physics, University of Texas at Austin
    • Department of Physics, University of Texas at Austin
    • University of Texas, Austin

  • Ping-Heng Tan

    • Institute of Semiconductors

  • Florian M Libisch

    • Vienna University of Technology

  • Xiaoqin (Elaine) Li

    • University of Texas at Austin
    • Physics, University of Texas at Austin
    • Department of Physics, University of Texas at Austin
    • U.T. Austin
    • Department of Physics, The University of Texas at Austin
    • Department of Physics, Center of Complex Quantum Systems, University of Texas at Austin

  View abstract →