It seems that the interface for the ACS journal changes every year. The instructions below are for the interface that is available as of May 15, 2009.
Click here to access ACS Journals
Within each search field, the Boolean Operators AND (also + or &), OR, and NOT (also -) perform searches that specify those logical relationships between terms. If no operator is entered, an AND relationship is assumed between each term entered except for the Author field (see Author Searching below).
To search for multiple authors, separate each author name with either AND or OR. Using AND will search for content that has been co-authored by the authors. Using OR will search for content that has been authored by either of the authors.
To bypass the default use of the AND relationship between the terms, enclose your terms in quotes. This will create a search for the specific phrase you have specified.
Wildcards allow you to construct a query with approximate search terms. Use a question mark (?) in a search term to represent any one character and use an asterisk (*) to represent zero or more characters. There are two limitations of wildcards: (1) they cannot be used at the beginning of a search term and (2) they cannot be used in a phrase enclosed in quotation marks.