The molar volume of silicon: discrepancies and limitations

We offer a new representation of the silicon molar volume discrepancy by attending to a previously incorrect accounting of the early work at the National Bureau of Standards (NBS). Removal of a poorly documented correction to the NBS density scale leads to a plausibly correct description of the molar volume anomaly problem. The possibility of discrepant metrology has been previously ruled out by sample exchanges. This led to several materials characterization exercises that gave important null results as briefly summarized here. We report the first non-null results and examine their correlation with those samples with discrepant molar volume values. In the end, there is a reasonably optimistic prospect that concordant and accurate density values can emerge at an interesting level of significance (less than 10 ^-7). A brief discussion of intrinsic limitations of melt-grown crystals is included