What Does a Chemist Do?

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S0001
Preparation for College Chemistry
Let's Talk Chemistry
Luis Avila avila_at_chem.columbia.edu Room Chandler
455 Phone [phone]
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What Does a Chemist Do?
What is Chemistry?

• Studies the atomic composition and structural
  features of substances.
• Investigates the varied interactions among
  substances
• Utilizes natural substances and creates
  artificial ones.
• Comprehends the complex chemistry of living
  organisms.
• Provides a molecular interpretation of health
  and disease.

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How Does She/He do it?
Main Divisions of Chemistry Organic Chemistry
Inorganic Chemistry Physical
Chemistry Analytical Chemistry Industrial
Chemistry (Chemical Engineering and Applied
Chemistry) Biochemistry
Materials Chemistry
Environmental Chemistry
Forensic Chemistry
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What is Organic Chemistry?
Largest area of specialization among the various
fields of chemistry
Synthetic Organic Chemistry

• Pharmaceutical Chemistry

• Polymer Chemistry

• Dye and Textile Chemistry

• Pulp and Paper Chemistry

• Agricultural Chemistry

• Formulation Chemistry (paint, food, petroleum
  products, adhesives, etc.)

Physical Organic Chemistry
Correlates the physical and chemical properties
of compounds with their structural features.
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We are interested in the multistep synthesis of
natural products, as well as the development of
new methodology, particularly to address problems
of regio- or stereocontrol. At present (1999), we
are working on problems suggested by structures
such as those of germine, taxol, cardenolides and
codeine
Synthetic Organic Chemist Professor Gilbert
Stork
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2-acetylnerifolin (class Cardenolide) Natural
Product with Antitumor Activity
Taxol Natural Product with Antitumor Activity
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Among our areas of current interest in the
anticancer field are epothilone and eleutherobin.
While structurally diverse, these two compounds
seem to function by a taxol-like mechanism in
their ability to inhibit microtubule
disassembly. Several projects are addressed to
goal systems with immunochemical implications.
Here we are particularly concerned with the
construction of a carbohydrate-based tumor
antigen vaccine.
Synthetic Organic Chemist / Bioorganic Chemist
Professor Samuel Danishefsky
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We deal with structural aspects of bioactive
compounds and elucidation of their mode of action.
In most cases this involves investigating the
interaction of small molecules with their
biopolymeric receptors. The recent dramatic
advancement in isolation, purification
and microspectroscopic methods has made it
possible for chemists to become involved in such
studies on a molecular structural basis
Natural Products Chemist Professor Koji
Nakanishi
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We view the photon as a reagent for initiating
photoreactions and as a product of the
deactivation of electronically excited molecules.
Our group is developing a novel field termed
"supramolecular" photochemistry, or
photochemistry beyond the conventional
intellectual and scientific constraints implied
by the term "molecule". In supramolecular
processes non-covalent bonds between molecules
play a role analogous to that of covalent bonds
between atoms.
Physical Organic Chemist / Photochemist Material
Chemist Professor Nicholas Turro
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What is Inorganic Chemistry?
Deals with the properties of elements ranging
from metals to non metals

• Organometallic Chemistry

• Bioinorganic Chemistry

• Ceramics and Glass

• Semiconductors

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We have a continuing interest in exploring
unusual artifacts resulting from X-ray
diffraction experiments (e.g. "bond stretch"
isomerism)
One of our interests is concerned with compounds
with metal-ligand multiple bonds, which are
species of considerable current interest in terms
of both their bonding and reactivity.
Organometallic Chemist / X-ray Spectroscopist
Professor Gerard Parkin
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In our major effort we are trying to prepare
artificial enzymes that can imitate the function
of natural enzymes.
A related study involves the synthesis of mimics
of antibodies or of biological receptor sites,
constructing molecules that will bind to
polypeptides with sequence selectivity in water,
using mainly hydrophobic interactions. These
could be very useful in modulating the activity
of peptide hormones, for instance.
Bio-organic Chemist Professor Ronald Breslow
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Measures, correlates, and explains the
quantitative aspects of chemical processes
What is Physical Chemistry?

• Theoretical Chemistry
• Devoted to Quantum and Statistical
  Mechanics.
• Theoretical chemists use computers to help them
  solve complicated
• mathematical equations that simulate specific
  chemical processes.

• Chemical Thermodynamics
• Deals with the relationship between heat,
  work, temperature,
• and energy of Chemical systems.

• Chemical Kinetics
• Seeks to measure and understand the rates
  of chemical
• reactions.

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Physical Chemistry

• Electrochemistry
• Investigates the interrelationship between
  electric current and chemical change.

• Photochemistry, Spectroscopy
• Uses radiation energy to probe and induce
  change within matter.

• Surface Chemistry
• Examines the properties of chemical surfaces,
  using instruments that can provide a chemical
  profile of such surfaces.

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My research is concerned with structural and
dynamic processes in condensed phase systems and
biomacromolecular systems.
Because the systems studied are often complex
many-body systems, it is necessary to utilize the
powerful analytical methods of statistical
mechanics as well as state-of-the-art methods of
computer simulation involving molecular dynamics
and Monte Carlo techniques.
Theoretical Chemist Professor Bruce Berne
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My research is materials, surfaces and
nanocrystals, especially in relation to optical
and electronic properties. This work can include
theoretical modeling, experimental chemical
physics, and synthetic chemistry. We try to
understand the evolution of solid state
properties from molecular properties, and to
create new materials with nanoscale structure by
both kinetic and thermodynamic self-assembly
methods.
Materials Chemist Professor Louis Brus
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Our research program involves the design,
synthesis, and detailed physical investigation of
novel molecular and nanoparticle materials which
display unique self-organized hierarchical
structures and specific optical, electronic,
and/or magnetic properties. Emphasis is placed on
materials with potential applications in
light-emitting devices, optical memory devices,
molecular level and single particle level
switching devices, and chemosensory devices. Our
research is necessarily interdisciplinary where
students and post-doctoral researchers are
exposed to modern aspects of inorganic, physical,
and materials chemistry.
Materials Chemist / Near Field Microscopist
Professor David Adams
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Experimental Physical Chemist / Surface Chemist
Professor George Flynn
We investigate molecular collisions that lead
either to chemical reaction or to the exchange of
energy between molecules. In particular, we have
developed the infrared diode laser absorption
probe technique to investigate collisions between
molecules.
We also study the structure of molecules
adsorbed on surfaces by using the Scanning
Tunneling Microscope (STM).
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What is Analytical Chemistry?
QUALITATIVE ANALYSIS deals with the detection of
elements or compounds (analytes) in different
materials. QUANTITATIVE ANALYSIS refers to the
measurement of the actual amounts of the analyte
present in the material investigated.

• Chemical and Biochemical Methods

• Gravimetry
• Titrimetric Analysis
• Enzymic Analysis
• Inmunochemical Analysis

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Analytical Chemistry

• Atomic and Molecular Spectroscopic Methods

• Nuclear Magnetic Resonance (NMR)
• Electron Spin Resonance (ESR)
• Mass Spectrometry (MS)
• Vibrational Spectroscopy (IR, RAMAN)
• X-Ray Fluorescence Analysis (XPS)
• Electronic Spectroscopy (UV, VIS, Luminiscence)
• Atomic Spectroscopy (AA, ICP)
• Rotational Spectroscopy (Microwave, FIR)

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Analytical Chemistry

• Chromatographic Methods (Partition equilibrium)

• Gas Chromatography (GC)
• High Performance Liquid Chromatography (HPLC)
• Gel Permeation Chromatography (GPC)
• Thin Layer Chromatography (TLC)
• Ion Chromatography

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Analytical Chemistry

• Thermal Methods

• Thermogravimetry (TG)
• Differential Thermal Analysis (DTA)
• Differential Scanning Calorimetry (DSC)
• Thermomechanic Analysis (TMA)

• Electrochemical Methods

• Electrogravimetry
• Electrophoresis
• Conductimetry,Potentiometry
• Polarography
• Voltammetry

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We study enzyme mechanisms using NMR. A variety
of experiments allow us to probe structural
details,dynamics or chemical details such as
protonation states.
In photosynthetic reaction centers, light energy
is converted to chemical potential energy through
long-range electron transfer events. A wealth of
crystallographic, mutagenic, and spectroscopic
work on these centers still leaves important
mechanistic questions unanswered.
Biophysical Chemist / NMR Spectroscopist
Professor Ann McDermott
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Our research interests center on the development
of selection strategies for identifying enzymes
from large pools of proteins.
This research is interdisciplinary, bringing
together the techniques of small-molecule
synthesis, molecular and cellular
biology, computer modeling, and mechanistic
enzymology and structural biology. The need for
efficient catalysts is fundamental. Biological
catalysts drive cellular processes, and the
chemical industry relies on catalysts for the
synthesis of compounds ranging from
pharmaceuticals to materials.
Molecular Biologist / Organic Chemist Professor
Virginia Cornish
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The Tools of the Trade
Periodic Table of the Elements
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Interesting Applications

• The KSC-ALS Breadboard Project
• Humans take in oxygen, food and water, and expel
  carbon dioxide and organic waste. Plants utilize
  carbon dioxide, produce food, release oxygen, and
  purify water. Inedible plant material and human
  waste are degraded by microorganisms to recycle
  nutrients for plants in a process termed resource
  recovery.

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When humans establish permanent bases on the
Lunar surface or travel to Space for exploration,
they need to develop systems to

• produce food
• purify their water supply and
• create oxygen from the carbon dioxide they expel.

Physico-chemical processes can perform the two
latter tasks, but only biological processes can
perform all three.
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• A life support system that would perform these
  regenerative functions, whether strictly by
  biological means or by a combination of
  biological and physical-chemical methods, has
  been called a Controlled Ecological Life Support
  System (CELSS).

• Biological systems utilize plants and
  microorganisms
• to perform these life support tasks in a
  process termed
• bioregeneration.

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A CELSS is a tightly controlled system, using
crops to perform life support functions, under
the restrictions of minimizing volume, mass,
energy, and labor.
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A career alternative for chemists, a
multidisciplinary arena to prove the role of
Chemistry as a "central science".