Thank you Steve for the syntax correction.
I have updated the xml file and executed the same. The liquibase was successful but the tablespace was not created.
$ liquibase --changeLogFile=/exports/atgtest/aeoadmin_scripts/update_atgncat.xml --defaultsFile=/exports/atgtest/liquibase-atgtest.properties upda
Liquibase Update Successful
The code is a below
<property name="dbname1" value="sit1" dbms="oracle" />
<changeSet author="KantamnenS" id="1">
<preConditions onFail="CONTINUE">
<and>
<sqlCheck expectedResult="1">select count(*) from v$database where name like '%SIT%'</sqlCheck>
<sqlCheck expectedResult="0">select count(*) from dba_tablespaces where tablespace_name like '%ATGCORE_DATA'</sqlCheck>
</and>
</preConditions>
<sql>
create tablespace atgcore_liquibase datafile '/u01/app/oracle/oradata/"${dbname1}"/atgcore_liquibase1.dbf' size 1G ;
</sql>
</changeSet>
</databaseChangeLog>