  The eigenstates of a quantum spin glass Hamiltonian with long-range
interaction are examined from the point of view of localisation and
entanglement. In particular, low particle sectors are examined and an anomalous
family of eigenstates is found that is more delocalised but also has larger
inter-spin entanglement. These are then identified as particle-added
eigenstates from the one-particle sector. This motivates the introduction and
the study of random promoted two-particle states, and it is shown that they may
have large delocalisation such as generic ran- dom states and scale exactly
like them. However, the entanglement as measured by two-spin concurrence
displays different scaling with the total number of spins. This shows how for
different classes of complex quantum states entanglement can be qualitatively
different even if localisation measures such as participation ratio are not.
