From chemistry-request@server.ccl.net Thu Jan 17 08:48:41 2002 Received: from ucidoor.unitedcatalysts.com ([208.23.162.2]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id g0HDmfI13746 for ; Thu, 17 Jan 2002 08:48:41 -0500 Received: by ucidoor.unitedcatalysts.com; (8.8.8/1.3/10May95) id IAA05913; Thu, 17 Jan 2002 08:48:29 -0500 (EST) Received: from 10.1.0.50 by ucismtp02.unitedcatalysts.com (InterScan E-Mail VirusWall NT); Thu, 17 Jan 2002 08:49:05 -0500 (Eastern Standard Time) Received: from lvlxch01.unitedcatalysts.com ([10.16.100.88]) by lvlmail.unitedcatalysts.com (PMDF V6.0-24 #41777) with ESMTP id <0GQ300FHZ4RNF6@lvlmail.unitedcatalysts.com>; Thu, 17 Jan 2002 08:42:59 -0500 (EST) Received: by lvlxch01.unitedcatalysts.com with Internet Mail Service (5.5.2650.21) id ; Thu, 17 Jan 2002 08:46:59 -0500 Content-return: allowed Date: Thu, 17 Jan 2002 08:46:58 -0500 From: "Shobe, Dave" Subject: RE: Is "Vibrational Spectroscopy" generally equals to "IR spectro scopy"? To: "'Zhenhua Li'" , chemistry@ccl.net Message-id: <157A51F55AAAD3119CD70008C7B1629D01C1586F@lvlxch01.unitedcatalysts.com> MIME-version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-type: text/plain; charset=gb2312 Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by server.ccl.net id g0HDmfI13747 My own opinion only: In practice "vibrational spectroscopy" is generally synonymous with "IR spectroscopy." However, there is a reason for having the 2 terms, since they are not *precisely* synonymous, and different concepts are involved in the 2 terms even if in practice the spectra being discussed are the same. "Vibrational" spectroscopy refers to the method in which the substance gains energy as a result of absorption: the energy goes largely into nuclear motions which involve changing of bond lengths & angles. "IR" (= "infrared") spectroscopy refers to the frequencies of electromagnetic energy being absorbed. As for "absorption" spectroscopy (I expect "adsorption" is a mistake, since I still get those words mixed up on occasion myself :-), this is an entirely separate issue. Absorption spectroscopy means that material is gaining energy at the expense of the electromagnetic field; emission spectroscopy means that the material is emitting energy as electromagnetic radiation. --David Shobe Süd-Chemie Inc. phone (502) 634-7409 fax (502) 634-7724 email dshobe@sud-chemieinc.com Don't bother flaming me: I'm behind a firewall. -----Original Message----- From: Zhenhua Li [mailto:lbbg123@etang.com] Sent: Wednesday, January 16, 2002 11:37 PM To: chemistry@ccl.net Subject: CCL:Is "Vibrational Spectroscopy" generally equals to "IR spectroscopy"? Hi, Dear listers, Today several staffs have a discussion about what is the implied or generally accepted meaning of "vibrational spectroscopy". One guy insisted that it is generally accepted that when we talked about vibrational spectroscopy, without specify IR or Raman before it, we must say that it is an "adsorption spectroscopy". But I insisted that any spectroscopy that originated from vibrational adsorption or emission can be called "vibrational spectroscopy". Thus, when we talked about "vibrational spectroscopy", we do not really means it is an IR spectroscopy. This is important since the meaning of this term has appeared in an exam paper. It is important to ensure not to give students wrong concept. Thanks a lot. Li Zhenhua -= This is automatically added to each message by mailing script =- CHEMISTRY@ccl.net -- To Everybody | CHEMISTRY-REQUEST@ccl.net -- To Admins MAILSERV@ccl.net -- HELP CHEMISTRY or HELP SEARCH CHEMISTRY-SEARCH@ccl.net -- archive search | Gopher: gopher.ccl.net 70 Ftp: ftp.ccl.net | WWW: http://www.ccl.net/chemistry/ | Jan: jkl@ccl.net