All of the databases appear to be where they should be. As an experiment, I tried tcp/ip to the 'posgres' database. That worked. Thanks to Ray, I worked that out. Per the suggestion I tried:
psql -h 127.0.0.1 -d d3_jchem. It connected after requesting a password (SSL). I still cannot connect to d3_jchem. Also, an additional role I created (su) was not found. Could it be a file protection setting. I notice that I cannot even ls the ..../base directory without being superuser. That does not seem right. Thanks for your patience and suggestions.
Dick