...I found a number of unpublished manuscripts and notes with varying degrees of approach to completion. All the documents show the characteristics of Platzman ’s work, i.e., the high level of scholarship, the vast knowledge of physics and chemistry, the great care for details, and the clear expression of thoughts. Platzman was a perfectionist; in other words, he sent out a manuscript for publication only after he felt that he had done the very best possible. He had an exceptional talent for the use of languages, including French and German, and yet devoted tireless efforts for producing the best-possible expression of his ideas in both writing and speech. Some of the materials in his files indeed show that he edited his manuscripts repeatedly until he was fully satisfied, and even reprints of his published papers, perhaps in the anticipation of revised publications. Therefore, it is with considerable hesitation that I publicly discuss the contents of the unpublished materials; he would vehemently disapprove the present act of mine. After deliberations I see now two reasons to defend it.

First, it has been nearly three decades since his death. Thus,he has become in effect a part of history, not personally known to a majority of current radiation scientists. His thought process deserves studies by future scholars. Second, the unpublished materials contain matters of continuing interest, amply showing both breadth and depth of his thoughts and work beyond his publications. Some of the documents listed below contain substantial ideas of current significance, at least in my view.

The titles of the unpublished manuscripts and notes include the following,expressed in his own words here indicated by quotation marks. The order of the documents listed is chosen merely for convenience of the present discussion, and has no deeper significance.
...
‘‘Fundamental Distinguishing Characteristics of the Biological and Chemical Action of Ionizing Radiation ’’
This manuscript of 22 pages is based on a talk given at the Conference on Certain Fundamental Aspects of Biophysical Science, held at Bethesda,Maryland on 15 January 1958,It is almost complete,reads nearly as well as his published papers, and contains ideas of present-day significance. Reading aloud the opening paragraphs, which are reproduced below, I almost hear Platzman ’s voice.

‘‘In little more than half-century, radiobiology has grown to be a major branch of biology, at least as measured by the extent of research effort. Part of current interest stems, of course, from pressing practical questions, such as implications in the field of public health of relentlessly rising radiation levels in food, air, and other material; problems of radiation accidents, a constant increase in which also seems inevitable; and medical effects (with their concomitant political overtones) of fission and fusion weapons, both present, in weapons testing, and future, in possible warfare.

The great and widespread activity in the field also devolves, in part, upon the circumstance that it is almost uniquely easy to carry out a new, and by present standards, publishable experiment in radiobiology: the effect of () radiation on the () property of the () system under () conditions. This ease is a commanding attraction and to it much of the aimlessness of the literature must doubtlessly be attributed.

But the paramount goal of radiobiology must be, of course, not the elucidation of radiation effects as such, but the exploitation of radiation to advance understanding of the familiar and fundamental biological phenomena. In attempting to direct efforts toward this goal it should be clearly helpful to characterize those features of the action of ionizing radiation which distinguish it from other modes of altering the behavior of biological systems.There are three such features, at the primary or physico-chemical level: track effects,formation of molecular states of very great electronic excitation energy, and the influence of the dielectric dispersion of the medium on its reaction to initial products. They will now be surveyed briefly, with particular emphasis on aspects which are presently either unknown or ill-understood ...’’

The passage of the second paragraph including the four blanks contains a satirical epigram. The blanks within the parentheses in the manuscript were left by Platzman, to be filled by the reader with any descriptors to generate titles of any number of papers. A similar remark may apply to radiation chemistry, too. Of the three ‘‘fundamental distinguishing characteristics discussed by Platzman, only the ‘‘track effects ’’are a part of general knowledge among current radiation scientists. The ‘‘formation of molecular states of very great electronic energy’’ is considered by some of them, and ‘‘the influence of dielectric dispersion'’ is appreciated by a few of them.

‘‘The Role of Dielectric Dispersion in the Action of Ionizing Radiation ’’
An almost complete manuscript of 17 pages, dated 14 April 1955,is substantial,and is significant even now. It presents a general discussion of the possible influence of the dielectric dispersion of a medium resulting from irradiation on the physics and chemistry leading to radiation effects.Examples include liquid water and proteins.Work on this topic does not seem to have been pursued as intensely as its importance warrants.

‘‘Remarks on the Concept of ‘Density of Ionization ’ in Radiation Chemistry and Biology ’’
An unfinished manuscript of 6 pages discusses the difficulties of evaluating the energy delivered per unit volume of an irradiated material,and points out errors found in the literature....

Full text: Scientific legacy of Robert L.Platzman.Preliminary report [.pdf], Mitio Inokuti, Radiation Physics and Chemistry 60 (2001)283 –290