  Rhombohedral La7Ru3O18 can be considered to be nearly geometrically
frustrated due to its close structural similarity to the strongly geometrically
frustrated compound La4.87Ru2O12. The magnetic ordering of La7Ru3O18 was
explored using a combination of dc and ac magnetic susceptibility measurements.
The magnetic phase diagram shows two different ordering regimes. A low field
magnetic phase occurs at applied fields of 0-3T and temperatures below 10K,
while a high field phase is found at fields of 3-5T and temperatures below 9K.
