R: Extracting charcters from string vectors to data frame rows

I have a data frame which has one colomn, a list of words. I’d like to extract the charcters from each word and have it stored as a position colomn in the data frame. For example, if the dataframe is defined like this:

words <- c('which', 'there', 'their', 'would') 
words <- as.data.frame(words)  

I’d like it to look like this at the end:

What I have so far is:

position <- c("first_pos", "second_pos", "third_pos", "fourth_pos", "fifth_pos")
words[position] <- NA
dismantled <- str_split(words$words,"")

This dismantles the words and creates the colomns I need. However, I could use some help filling the rows of the colomns with the letters.

>Solution :

We could use separate after a space between each character in words:

library(tidyverse)
words %>%
  mutate(words1 =  sub("\\s+$", "", gsub('(.{1})', '\\1 ', words))) %>% 
  separate(words1, into = paste0(1:5, "_pos"))

  words 1_pos 2_pos 3_pos 4_pos 5_pos
1 which     w     h     i     c     h
2 there     t     h     e     r     e
3 their     t     h     e     i     r
4 would     w     o     u     l     d