DIR ..
  TEXT density.txt                                              1.2K 2026-03-13 17:17 UTC
   BIN elements.csv                                            20.5K 2026-03-13 17:17 UTC
   BIN families.csv                                             4.2K 2026-03-13 17:17 UTC
  TEXT periodic.txt                                             4.1K 2026-03-13 17:17 UTC
   BIN shells.csv                                               1.1K 2026-03-13 17:17 UTC
   BIN sources.csv                                              257B 2026-03-13 17:17 UTC