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Chemistry Overview
avila_at_chem.columbia.edu Room Chandler 455 Phone
[phone] Columbia University Department
of Chemistry
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(No Transcript)
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What Does a Chemist Do?

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

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How Does S(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
Concerned with the correlation of the physical
and chemical properties of compounds with their
structural features.
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We are primarily engaged in the invention and
development of stereoselective catalytic
reactions and the total synthesis of biologically
active and structurally complex natural products
Synthetic Organic Chemist Professor James
Leighton
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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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Zinc is a constituent of more than 300 enzymes.
The active sites of these enzymes feature a zinc
center attached to the protein backbone by three
or four amino acid residues, the nature of which
influences the specific function of the enzyme.
In order to understand why different zinc enzymes
utilize different amino acid residues at the
active site, it is necessary to understand how
and why the chemistry of zinc is modulated by its
coordination environment. Answers to these
questions are being provided by a study of small
molecules that resemble the enzyme-active sites.
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 http//www.oit.doe.gov/cfm/fullarticle.cfm
/id743
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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 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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Experimental Physical 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.

• Gravimetry
• Titrimetric Analysis
• Enzymic Analysis
• Inmunochemical Analysis

Chemical and Biochemical Methods
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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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The Tools of the Trade
Periodic Table of the Elements
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The Tools of the Trade
Periodic Table of the Elements http//www.spectros
copynow.com/Spy/tools/periodic.html
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Interesting Applications

• The KSC-ALS Breadboard Project
• Uses biological systems to recycle material
  through a ALS (Advanced Life Support) system.
  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 physico-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.