Polywater. Comments - ACS Publications

Oct 25, 1971 - bond length ratio in the matrix accrues when anhar- monicity is compensated for by applying the appro- priate anharmonic constants obta...
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456 shown in Table 111,no improvement in the value of the bond length ratio in the matrix accrues when anharmohicity is compensated for by applying the appropriate anharmonic constants obtained from the overtone-combination analysis in the gas phase16although the gas phase data shomd excellent consistency whcn this correction was applied.

Table I11 : Ratios of Gas Phase and Matrix Bond Lengths Calculated from the Observed and Harmonic Frequencies Using the Redlich-Teller Product Rule ---Gasa--7 -

Matrix---

--(TCN/TCH)---

Observed

13armonio

Observed

Harmonk

1.01

0.96 i 0.03

1.145

1.079

0.99

0.97 f 0.03

1.116

1.082

1.13

1.09 =k 0.02

1.119

1.081

1.07

1.05 f 0.02

1.095

1.081

0.91

0.85 3= 0.05

1.169

1.077

0.93

0.89 i 0.05

1.135

1.082

1.00

0.97

0.04

1.130

1.080

--(TcN/TcH)----

=k

Microwave measurements give a value 1.083 for this ratio.

It does not seem plausible that the discrepancies of the isotope shifts can be accounted for by a change in the geometry of HCK in argon. The van der Waals forces that exist between the molecule and the matrix environmect are not strong enough to deform the HCN bonds 0.1 A. The discrepancy most likely results from the failure of the linear x-y-x vibrational model to describe the vibrations of the matrix isolated molecule adequately. If this is true, one is forced to conclude that molecular geometries based on the analysis of isotopic shifts in matrices are likely to be in serious error when light isotopic substitutions are involved, e.g., H and D, no matter how precisely the frequencies are measured and no matter how well anharmonicity is accounted for. INSTITUTE FOR ATOMIC RESEARCH DEPAR.TMENT OF CHEMISTRY IOWA STATEUNIVERSITY AMES,IOWA50010 AND

Polywater Publication costa assisted by the Naval Research Laboratory

Sir: Recently, Brummer, et aL,l gave a detailed description of their procedure for preparing “polywater” or anomalous water in high yields. Their results may be interpreted as merely adding to t,he evidence that this material is not a modified or polymeric form of water but is simply the corrosion product of the Pyrex or quartz capillaries in which it is formed as suggested by Bascom, Brooks, and Worthington.2 One of the principal points made by Brummer, et al., is that the yield of “polywater” is greatest in strained regions of the glass or quartz capillary. For example, their yield was particularly high at the tapered ends of thick walled capillaries that had been sealed by melting and drawing. Annealing the capillaries removed this enhanced activity. In the earlier work of Bascom, et U Z . , ~ it was pointed out that strained siloxane bonds would be especially susceptible to attack by adsorbed mater made alkaline by cations present in the Pyrex (or in the case of quartz by electrolytes that had surface-diffused into the capillaries). The product of this surface corrosion would be an alkaline silicate sol or gel. Brummer, et al., and others before them3 claim that the infrared spectrum of “polywater” is unique and cannot be attributed to inorganic salts. However, Bascom, et al., have shown that spectra of bicarbonatesilicate mixtures closely resemble the polywater spectra. They argue that the alkaline condensate formed in glass and silica capillaries absorbs atmospheric COZ to form the bicarbonate ion. An example of the bicarbonatesilicate spectra is given in Figure 1. It closely resembles the spectrum of the Pyrex-grown polywater given by Brummer, et al. (Figure 2C, reference 1). The bands at! 1650 cm-l and 1425 cm-’ originally attributed to “ p ~ l y w a t e r ”are ~ due to the symmetric and antieymmetric 04-0 stretching vibrations. The band at 1000-1100 cm-l is due to the Si-0-Si stretch of the silicate constituent. This band and the sharp bands between 800 and 900 cm-l are also present in the “polywater” It should also be noted that the 1425-cm-’ band appears to be a doublet in both the bicarbonate-silicate spectrum and the “polywater” spectra. The salt solution used to obtain Figure 1 was made by mixing equal amounts of a 10% (by weight) solution of KHC03 and a 15% solution of SiOz and Na~Si03at a 3.3: 1 mole ratio. This mixture was diluted to about 0.5% with distilled water. Approximately 0.25 ml of this final solution was then dried to a gel on an Irtran

JACOB PACANSKY (1) 8 . B. Brummer, G. Entine, J. I. Bradspies, H. Lingertat, and G. VINCENT CALDER* C. Leung, J. Phys. Chem., 75,2976 (1971). (2) W. D. Bascom, E. J. Brooks, and B. N. Worthington, Nature

RECEIVED OCTOBER 25, 1971 The Journal of Physical Chemistry, Vol. 76, No. 3, 197d

(London), 228, 1290 (1970). (3) E. R. Lippinoott, R. R. Stromberg, W. H. Grant, and G. L. Cessao, Science, 169, 1482.(1969).

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457

WAVENUMBFR ICM 1

WPVENUMEER (CM ’)

Figure 1. Infrared spectrum of the residue of a bicarbonate-silicate solution.

plate. As noted previously2 the positions and the relative intensities of the bands depend on the composition and the history of the bicarbonate-silicate mixture. It would appear that “polywater” could easily result from the surface corrosion of the capillaries to form an alkaline product that absorbs COz from the air. This explanation reasonably accounts for the reported presence of carboxylic acid groups4 and a high carbon content6 of polywater samples. Furthermore, we would expect a solution of inorganic ions to increase the surface tension of water-a property recently attributed to anomalous water.6 Finally, “polywater” formed from D20 has an infrared spectrum identical with that of Hz07 which is difficult to understand if the material is a polymeric form of water but easily explained if it is a mixture of bicarbonate and silicate ions. There are objections to explaining “polywater” in terms of bicarbonate-silicate mixtures. Rousseau’ notes that when compared to the “polywater” spectra, the bicarbonate band is at 1650 cm-1 rather than at 1600 cm-l and that the 1400-cm-’ band tends to be the more intense of the two whereas it is usually the opposite in the polywater spectra. However) recent spectra claimed for “polywater” show the 1400-cm-l band to be equal or stronger than the 1 6 0 0 - ~ m -band1g6 ~ and in one case6 the latter band appears to be shifted to a higher frequency. (4) R. E. Davis, D. L. Rousseau, R. 0. Board, Science, 171, 167 (1971). (5) T. F. Page, and R. J. Jakobaen, J. Colloid Interface Sci., 36, 427 (1971). (6) B. V. Deryagin, 2. M. Zorin, V. V. Karasev, V. D . Sobolev, E. N. Khromova, 4nd N. V. Churaev, Dokl. Akad. Nauk SSSR, 187, 608 (1969). (7) D. L. Rousseau, J . Colloid Interface Sei., 36, 434 (1971). SURFACE CHEMISTRY BRANCH CODE6170, CHEMISTRY DIVISION NAVALRESEARCH LABORATORY WASHINOTON, D. C. 20390

BECEIVED OCTOBER 26,

Polywater, a n Organic Contaminant Publication costs borne completely by The Journal of Physical Chemistry

Sir: Bascom raises two important points about anomalous water-that it is not polymeric water and that it is in fact dissolved glass, specifically a silicate-bicarbonate residue. It is pertinent to examine the evidence for thesc views. The only remaining evidence of any substance to suggest that anomalous water may be polymeric mater is that of Deryagin, et a1.l We have attempted to reproduce many of their results, including the quantitative conversion of anomalous water to water, and the preparation of anomalous water under conditions of rigorous organic exclusion. Our findings do not agree with the Russian work and we concur with Bascom that anomalous water is not a polymeric form of water. However) we disagree with the proposal that the phenomenon is due to an inorganic contaminant, in particular silicate-bicarbonate. Thus, both Rousseau2 and Lippincott, et aL13have shown conclusively that there was very little silicon in their material. In addition, we have produced anomalous water from a ZrOz-based glass (Corning #7280) which does not exhibit the 1000llOO-cm-l ir band attributed to silicate (Figure 1). We would say also that the ir spectrum on which Bascom bases his argument is not typical of the anomalous water spectrum. Thus, his band at -1650 cm-l is more usually found at -1590 cm-l-except, we have found, on acidification, when it shifts to -1700 cm-‘ and the material becomes volatile in the ir beam, which behavior is typical of carboxylic acids. Also, his spectrum shows a peak at -880 cm-’. This peak is characteristic of ionic carbonate and would be expected to oc-

WILLARD D. BASCOM (1) B. V. Derjaguin and N. V. Churayev, J . Colloid Interface Sci., 36, 415 (1971).

1971

(2) D. L. Rousseau and 5. P. 8.Porto, Science, 167, 1715 (1970). (3) E. R. Lippincott, R. R. Stromberg, W. H. Grant, and G. L. Cessac, Science, 164, 1482 (1969).

The Journal of Physical Chemistry, Vol. 76,No. S, 1973