Papers published by the American Chemical Society (ACS) under their Open Choice option are now available in PMC and UKPMC. Currently around 110 papers - drawn from 20 ACS journal titles - are now freely available. These papers can be found by running the following search on UKPMC:
ACS Author Choice [filter]
All future papers published under this model will be made available through these repositories at the time of publication.
ACS Open Choice articles are fully open access in the sense that the licence [PDF link] allows users - for non-commercial research and education purposes - to "access, download, copy, display and redistribute articles as well as adapt, translate text and data mine the content...."
This model meets the requirements of the Wellcome Trust - and the other funders in the UKPMC Funders Group.