Teaching Quantum Concepts
in General Chemistry
with Interactive Computer Software
Alan D. Crosby1 – (acrosby@bu.edu)
Peter Carr2
Luciana S. Garbayo2
Alexander Golger1
Dan Dill1
Peter S. Garik2
Morton Z. Hoffman1
1Department
of Chemistry, Boston University
2School of Education, Boston University
http://quantumconcepts.bu.edu
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What’s the problem with teaching
Quantum Concepts in general chemistry?
 Anti-intuitive with respect to the
macroscopic world
 Demands the suspension of belief
 Historical presentation in text books
 Supporting graphics paint misleading
and inaccurate images
 Perpetuation of misconceptions
2
What’s the problem with teaching
general chemistry?
 Passive learning with the lecture format
 Solitary learning is the norm
 Large discussion sections become mini-
lectures
 TA’s are often from different cultural,
educational, and linguistic backgrounds
 Textbooks are voluminous, and
increasing in content
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Do we really need to teach Quantum
Concepts in general chemistry?
 The future belongs to the quantum
 Nano-technology
 Quantum lasers
 Quantum computers
 The foundation of modern science
 Molecular medicine and drug design
 Biochemical interactions
 Beyond general chemistry
 Organic
 Inorganic
 Physical
 Biochemistry
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What to do?
 Develop materials to enhance learning
 Change the pedagogy to promote active
learning
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Project design: basic principles
 Quantum concepts unify the teaching
of general, organic, inorganic, and
physical chemistry.
 Quantum concepts force us to
confront how we know what we know
about the physical world.
 Students learn best through direct
exploration and discovery.
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Project summary
 Visually oriented tools based on real-
time rigorous numerical calculations.
 Fun to use while discovering and
exploring key features of fundamental
quantum concepts.
 Enable students to grasp the essence of
the quantum concepts.
 Builds a foundation upon which the
teaching of modern chemistry is based.
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Current project modules
 Schrödinger Shooter
 Energy levels and wavefunctions that are solutions
to the Schrödinger Equation in a given potential.
 Atomic Explorer
 Energy levels and shapes of atomic orbitals.
 Bond Explorer
 Bonding and energy levels for overlapping atomic
orbitals to create molecular orbitals.
 Diatomic Explorer
 Bonding and energy levels for diatomic molecules.
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Project modules in development
 Hybridization Explorer
 Potential energy surfaces and the force field that
results in the directional bonding of key elements
(e.g., B, Be, C, N, and O).
 Reactivity Explorer
 An extension of the concepts developed in the
Bond and Hybridization Explorers; examine the
force field that determines the reaction sites.
 Spectral Explorer
 Display laboratory spectra and compare with
spectra that can result from energy transitions
between molecular or atomic energy levels.
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Curriculum reform
 Use of peer-led workshop model in honors
level general chemistry
 Required reading of text and supplementary
material
 Detailed discussions, group activities, and
demonstrations in lecture section
 Workshops on quantum concepts
Development of semi-quantitative
understanding
Use of interactive software for active
learning
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Group investigations
 Discussion of wavefunction value, curvature, and
kinetic energy (the Schrödinger Equation) without
mathematics:
curvature of ψ ∝ - kinetic energy × ψ
 Sketching of wavefunctions for different simple
potential energy functions:
 Free electron
 Linear ramp potential
 Infinite vertical wall (particle in a box)
 Finite vertical wall (particle “escapes”)
 Variation of total energy
 Normalization
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Where are we?
 Current application of PLTL
Honor-level general chemistry
Physical chemistry/quantum concepts
Inorganic chemistry
 Development of advanced materials for
physical chemistry based on the
modules
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Where are we going?
 PLTL across the curriculum
 Introduction of the modules in other
courses
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“Shooter” workshop overview
 Part I – develop understanding
 Qualitative “feel” for the Schrödinger Equation;
qualitative and semi-quantitative interpretation.
 Physical interpretation of potential energy
functions, wavefunctions, and probability.
 Free-hand sketching of expected wavefunctions
for simple potential energy functions.
 Part II – use the Schrödinger Shooter
 Verify the results from Part I.
 Examine more realistic potential energy functions.
 Collect energy values as functions of quantized
parameters.
 Discover the origin of quantum numbers.
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Acknowledgements
Project funding:
 Current: US Department of Education, Fund for the
Improvement of Post Secondary Education
(FIPSE), Award P116B020856, "Exploring Quantum
Concepts in Chemistry: Active Discovery by
Students in the General Chemistry Course."
 Previous: NSF Grant REC 9554198 and a NSF
minigrant subcontract from the University of
Northern Colorado (REC-0095023).
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How the Schrödinger shooter works
 Real-time Cooley-Numerov integration
 Many potential energy functions
 Adjustable interface of parameters
 Multiple views and visualizations:
Value of the wavefunction (amplitude)
Amplitude squared (probability)
Range of parameters
Potential, kinetic, and total energy depiction
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