I noticed that in borei nefashot in the Artscroll Siddur and in the Koren Siddur the tav in word בראת has no dagesh. I was under the impression that the tav suffix for second person masculine past always had a dagesh so I was wondering why this might be.
The tav is one of the beged kefet letters, which always takes a dagesh kal, when it starts a new syllable after a previously closed one (i.e. the previous syllable ends with a consonant).
To quote from the relevant Wikipedia article:
In Hebrew writing with niqqud, a dot in the center of one of these letters, called dagesh ( ּ ), marks the plosive articulation:
- at the beginning of a word or after a consonant (in which cases it is termed "dagesh qal")
Generally, you are correct, in that for most verb types the tav suffix for second person masculine singular starts a new syllable after the previous syllable is closed by a consonant e.g. שמרת , לקחת.
However, for a ל"א verb such as ברא, the aleph in בראת does not close the syllable, and thus the tav takes no dagesh. For another example, see this week's parsha (Shemot 33:17):
כִּי-מָצָאתָ חֵן בְּעֵינַי
The tav at the end of מצאת has no dagesh, as the א does not close the previous syllable.
This also occurs with ל"ה verbs e.g. עשה. See all the instances of ועשית at the beginning of last week's parsha for example.