IEC TR 62456:2007
(Main)An electrochemical reference system for use in different solvent media - The decamethylated ferricinium/ferrocene redox couple
An electrochemical reference system for use in different solvent media - The decamethylated ferricinium/ferrocene redox couple
to present the background considerations which led to this compilation of potentials of the aqueous saturated calomel electrode compared to the cyclovoltametric data for a glassy carbon electrode in various solvent media. A tabulation of working potentials of this electrode pair in various solvent media is presented. A comparison of the cyclovoltametric scans for the ferricinium/ferrocene and deamethyl derivatized ferricinium/ferrocene redox couple system is presented and important features are discussed
General Information
Standards Content (Sample)
TECHNICAL IEC
REPORT TR 62456
First edition
2007-03
An electrochemical reference system
for use in different solvent media –
The decamethylated ferricinium/ferrocene
redox couple
Reference number
IEC/TR 62456:2007(E)
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.
Consolidated editions
The IEC is now publishing consolidated versions of its publications. For example,
edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
Further information on IEC publications
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology. Information relating to
this publication, including its validity, is available in the IEC Catalogue of
publications (see below) in addition to new editions, amendments and corrigenda.
Information on the subjects under consideration and work in progress undertaken
by the technical committee which has prepared this publication, as well as the list
of publications issued, is also available from the following:
• IEC Web Site (www.iec.ch)
• Catalogue of IEC publications
The on-line catalogue on the IEC web site (www.iec.ch/searchpub) enables you to
search by a variety of criteria including text searches, technical committees
and date of publication. On-line information is also available on recently issued
publications, withdrawn and replaced publications, as well as corrigenda.
• IEC Just Published
This summary of recently issued publications (www.iec.ch/online_news/ justpub)
is also available by email. Please contact the Customer Service Centre (see
below) for further information.
• Customer Service Centre
If you have any questions regarding this publication or need further assistance,
please contact the Customer Service Centre:
Email: custserv@iec.ch
Tel: +41 22 919 02 11
Fax: +41 22 919 03 00
TECHNICAL IEC
REPORT TR 62456
First edition
2007-03
An electrochemical reference system
for use in different solvent media –
The decamethylated ferricinium/ferrocene
redox couple
© IEC 2007 ⎯ Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale H
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue
– 2 – TR 62456 © IEC:2007(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
AN ELECTROCHEMICAL REFERENCE
SYSTEM FOR USE IN DIFFERENT SOLVENT MEDIA –
THE DECAMETHYLATED FERRICINIUM/FERROCENE
REDOX COUPLE
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example, "state of the art".
IEC 62456 which is a technical report, has been prepared by subcommittee 65D: Analysing
equipment, of IEC technical committee 65: Industrial-process measurement and control.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
65D/125/DTR 65D/127/RVC
Full information on the voting for the approval of this technical report can be found in the report
on voting indicated in the above table.
TR 62456 © IEC:2007(E) – 3 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until the
maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
– 4 – TR 62456 © IEC:2007(E)
INTRODUCTION
The proposal of this technical report is justified by the difficulties met by electrochemists,
electroanalysts, corrosionists, and biologists when electrode potentials measured in different
non-aqueous or aqueous-organic solvents with reference to the familiar, commercially
available, and very dependable, aqueous Saturated Calomel Electrode (SCE) are to be
physically inter-compared on some “inter-solvental scale” of electrode potentials. These
difficulties are caused by the occurrence of two basic extrathermodynamic factors, namely, the
primary medium effect [1] on electrode potentials and the liquid-junction potentials between
different solvent media. This report details the use of the half-wave potential of the
ferricinium/ferrocene redox couple or the decamethyl derivatized ferricinium/ferrocene redox
couple as the basis of a reference electrode system useful to compared measured electrode
potentials to the aqueous saturated calomel electrode when used in various solvent systems.
For an acceptable approach to the solution of the above problem, superseding earlier attempts
[2], Strehlow and co-workers [3], [4] proposed to use the redox couple ferricinium|ferrocene (in
terms of its “half-wave potentials”, or “formal redox potentials”, obtainable from voltametric
experiments in different solvents with the same supporting electrolyte and against the same
working reference electrodes), for which, based on an extended experimental evidence, they
assessed an “invariancy of potential” to within about ±15 mV in a dozen different solvents,
assuming the above redox couple to be unaffected by solvent interactions. Principles and
reasons for this choice were expounded in detail [3], [4] and need not be repeated
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.