Subject: RE: Alternant hydrocarbons and the film "My Fair Lady"

From: "Shobe, Dave" <[email-masked]>
Date: Thu, 13 Sep 2001 10:12:03 -0400

Guess what?  Even mathematicians studying graph theory (roughly, the
mathematics of line drawings, connectivity, and networks) do not use the
word "alternant".  Their term is "bipartite".  

Your definition of "alternant" or "bipartite" is missing an important point:
either word means that the vertices/nodes/atoms can be divided into two sets
(starred/unstarred or red/blue or whatever) with the property that no two
"adjacent" vertices are in the same set.  "Adjacent" means that there is a
line/edge/bond between the two vertices/atoms.  
Especially when explaining to children, it might be good to have them, as an
exercise, try to do this division into two sets for different
graphs/pi-systems, e.g. naphthalene and azulene.  They might even discover,
on their own, the relationship between alternant-ness and odd cycles.

Computational chemistry is more holistic than you might think.  One of the
problems in computing large molecules is that the wave function of the
electrons extends across the entire molecule and even outside of it.  If you
put several molecules together, there is one wave function for the entire
system.  It is the job of the theoretical chemist (not quite the same as
computational chemist, although there is a large overlap between the two
professions) to come up with reductionistic explanations of quantum systems
in terms of bonds, interatomic forces, etc. where these are appropriate.  

In many areas we're still finding new ways to put the "Legos" together. On
the other hand, the world's synthetic chemists are indeed making complex and
interesting structures from the building blocks.  Some of them imitate
natural structures, while others are abstract.

--David Shobe
Süd-Chemie Inc.
phone (502) 634-7409
fax     (502) 634-7724
email  [email-masked]

Don't bother flaming me: I'm behind a firewall.

-----Original Message-----
From: Henry Pang [mailto:[email-masked]]
Sent: Wednesday, September 12, 2001 4:42 PM
To: [email-masked]'
Cc: [email-masked]'
Subject: CCL:Alternant hydrocarbons and the film "My Fair Lady"

Hi CCL

I am interested to find out if my impression CC is a super reductionist
field is reasonable. The word "alternant" is found in CC books. Ira Levine
(1983), Quantum Chemistry says, "An alternant hydrocarbon is a planar
conjugated hydrocarbon in which the carbon atoms can be divided into a
starred set and an unstarred set."

My several general chemistry books do not mention alternant. I do not find
any entry for "alternant hydrocarbon" in the Cambridge International
Dictionary of English, Academic Press Dictionary of Science and Technology,
but the Concise Oxford Dictionary says, "alternant is alternating, of
alternating layers". I do not find any mention in books of cosmology,
astronomy, physics, archaeology, anthropology, history, language,
linguistics, law, medicine, surgery, politics, metal work, or mass media for
example.

I do have some idea; alternant is interesting in molecules such as
cyclobutadiene, naphthalene, benzyl radical, azulene, cyclopentadienyl
radical. I am looking for any discussion regarding what the word "alternant"
means in plain English, which other people in the university and community
might appreciate as human beings, even though not expert in CC.

Please understand I am not being disrespectful or even facetious. Do you
recall the award film "My Fair Lady"? Common flower girl Eliza Doolittle
asks phonetics expert Professor Higgins to teach her to speak like a lady.
Eliza becomes the belle of British society and the Prince takes her hand to
lead her to the dance floor at the great Ball. Higgins takes all the credit.
As he says, "I knew I could do it." He tells Eliza, but she replies in total
defiance, "I do not understand anything you are saying to me. I am too
ignorant!"

I am not CC, but just an Australian medical doctor. I am just curious about
CCL. Forgive me, but CCL seems like an intense activity looking the computer
measurements and bond strengths of the Lego blocks put together by my
children into interesting creations. CCL day in and day out, seems about
finding better ways of computing the minute details of my children's Lego
blocks?

Questions -
1.Have you any material, which explains "alternant" in plain English for my
children, so they might really understand what the animal is in real terms?
2.Have you ever heard of another word "Holism"? Could holism be of any
interest to the super reductionist field of CC? Does it really matter to the
world or our Universe in any case?

(I am disgusted and very sad about New York and the Pentagon)

Regards
Dr Henry Pang (medical) 
Australia

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