From: Geoff Howlett <ghowlett@unimelb.edu.au>
  To  : rasmb@alpha.bbri.org
  Date: Thu, 28 Sep 2000 09:43:55 +1000

responses to viscosity of D2O

Hi All

Thank you to all those who responded re. the viscosity of D2O.  A summary:

1.      From: Urbanke.Claus@mh-hannover.de
I do have a photocopy of graph for the viscosity of heavy water vs.
temperature where unfortunately the source is untraceable. It tells me that
a 20 C the viscosity is 1.25E-3 N s m^-2.  (This gives an eta relative at=20
20 deg of approx 1.25)

2.      From: Christine EBEL <Christine.Ebel@ibs.fr>
Landolt-B=F6rnstein, Springer Verlag, Berlin, 1969, Band II, Teil 5,=
 Bandteil=20
5a, p131:
For temp: 15, 20, 30, 40=B0C; eta: 1,405, 1,277, 1,033, 0,807 cp (eta=20
relative at 20 deg 1.274)

3.      From: J=F6rg Langowski <jl@dkfz-heidelberg.de>
Here it is:
http://www.embl-heidelberg.de/~bottomle/viscosity.html
thus, at 25 oC D2O is 1.349 times more viscous than water.

4.      From: Gordon Lucas <lucas@mpikg-golm.mpg.de>
I use a value of 0.01095 at 25 degrees for D2O, which is a little bit=20
higher than for water, but I don't have a reference for that. (eta relative=
=20
of 1.23)

5.      From: John Philo <jphilo@mailway.com>
By now you may have heard this from others, but the viscosity of D20 is
considerably (~25%) higher than for H20. From what Art Rowe said I guess
we'll get some updated values soon, but anyway here are some data I found
for the viscosity ratio, D20/H20 versus temperature:
20              1.249
25              1.232
(eta relative at 20 deg of 1.25)
6.      From: Jacob Lebowitz <lebowitz@helix.nih.gov>
There are very large viscosity and density corrections when using D2O or=20
D2O:H2O mixtures. I have attached a table:
Density and Relative Viscosity Values of Volume Percent Mixtures of Pure=20
D2O and H2O at 20oC from Kirschenbaum, I. Physical Properties and Analysis=
=20
of Heavy Water, pp.1-41. New York, McGraw-Hill, 1951.
%D2O byVolume   eta relative
100     1.2465

I have followed up Arthur Rowe's suggestion of seeking more recent=20
values.  At this stage the consensus appears to be a figure of eta relative=
=20
of 1.25.

Thanks again to all who responded.

Best wishes

Geoff Howlett















Department of Biochemistry and Molecular Biology
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